Physics (IGCSE) Revision

Reviewed by Editorial Team
The ProProfs editorial team is comprised of experienced subject matter experts. They've collectively created over 10,000 quizzes and lessons, serving over 100 million users. Our team includes in-house content moderators and subject matter experts, as well as a global network of rigorously trained contributors. All adhere to our comprehensive editorial guidelines, ensuring the delivery of high-quality content.
Learn about Our Editorial Process
| By Geniusasis
G
Geniusasis
Community Contributor
Quizzes Created: 1 | Total Attempts: 2,573
| Attempts: 2,573 | Questions: 71
Please wait...
Question 1 / 71
0 %
0/100
Score 0/100
1. Sound waves are caused by vibrations

Explanation

Sound waves are caused by vibrations. When an object vibrates, it creates a disturbance in the surrounding medium, such as air or water. This disturbance travels in the form of waves, which we perceive as sound. The vibrations cause the particles in the medium to oscillate back and forth, transmitting energy and creating the sound waves. Therefore, it is true that sound waves are caused by vibrations.

Submit
Please wait...
About This Quiz
Physics (IGCSE) Revision - Quiz

This IGCSE Physics quiz assesses key concepts such as work done, kinematics, inertia, pressure in liquids, power conversion, and acceleration. It is designed to reinforce students' understanding and... see moreprepare them effectively for their exams. see less

2. Diaomond does not conduct electricity because it does not have any free electrons.

Explanation

Diamond is a covalent network solid composed of carbon atoms bonded together in a tetrahedral lattice structure. Each carbon atom forms four strong covalent bonds with its neighboring atoms, leaving no free electrons to move and conduct electricity. Therefore, diamond is an insulator and does not conduct electricity.

Submit
3. Force = ___________ x ________________

Explanation

The equation F=ma represents Newton's second law of motion, which states that the force acting on an object is equal to the mass of the object multiplied by its acceleration. This means that the force experienced by an object is directly proportional to both its mass and the rate at which its velocity changes. Therefore, F=ma is the correct equation to calculate force.

Submit
4. Any frequency over the limit of 20,000Hz is called an ultralsound frequency.

Explanation

Any frequency over the limit of 20,000Hz is called an ultralsound frequency. This statement is true because ultrasonic frequencies are those that are higher than the upper limit of human hearing, which is typically around 20,000Hz. Ultrasonic frequencies are commonly used in various applications such as medical imaging, cleaning, and pest control.

Submit
5. An on shore breeze is caused because land warms faster and reatains its heat worse than water since it has a greater heat capacity, causing warm air to rise and cool air to sink casuing a convection current.

Explanation

The explanation for the given correct answer is that an onshore breeze is indeed caused by the land warming faster and retaining its heat worse than water. This is because land has a greater heat capacity compared to water. As a result, warm air rises over the land and cool air sinks over the water, creating a convection current that leads to an onshore breeze.

Submit
6. Boyle's Law is symbols : p1V1=p2V2. True or False

Explanation

Boyle's Law states that the pressure and volume of a gas are inversely proportional to each other at a constant temperature. The equation p1V1 = p2V2 represents Boyle's Law, where p1 and V1 are the initial pressure and volume, and p2 and V2 are the final pressure and volume. Therefore, the statement "Boyle's Law is symbols: p1V1 = p2V2" is true.

Submit
7. Passing current through a wire produces a circular magnetic field, while passing current through a coil acts as a magent.

Explanation

Passing current through a wire does indeed produce a circular magnetic field, as stated by Ampere's law. This is because the flow of electric current creates a magnetic field that wraps around the wire in a circular pattern. Similarly, when current is passed through a coil, it acts as a magnet due to the magnetic field produced by the flow of current. This phenomenon is utilized in electromagnets, where a coil of wire is wrapped around a core material to enhance the magnetic field strength. Therefore, the statement is true.

Submit
8. Photocopiers use the principle of electrostatic charges

Explanation

Photocopiers use the principle of electrostatic charges to create copies of documents. This principle involves the use of a photosensitive drum that is charged with static electricity. When a document is placed on the glass surface of the copier, light is shone onto it, causing the areas that reflect light to become positively charged and the areas that do not reflect light to remain negatively charged. These charged areas attract toner particles, which are then transferred onto a piece of paper to create a copy of the original document. Therefore, the statement "Photocopiers use the principle of electrostatic charges" is true.

Submit
9. Leaving air gaps makes a good insulator

Explanation

Leaving air gaps creates pockets of trapped air, which is a poor conductor of heat. This trapped air acts as an insulator, preventing the transfer of heat through conduction. Therefore, leaving air gaps can indeed make a good insulator.

Submit
10. Commutators are used in motos to the coil to change current direction every half turn.

Explanation

Commutators are indeed used in motors to change the direction of current flow in the coil every half turn. This is necessary for the motor to generate continuous rotation. By periodically reversing the current direction, the magnetic field produced by the coil also reverses, causing the rotor to rotate in one direction. Therefore, the statement is true.

Submit
11. Principle of moments says describes that: the sum of the _________a_________  moments about any point is equal to the sum of ________b_______ moments abouth that point.

Explanation

The principle of moments states that the sum of the clockwise moments about any point is equal to the sum of the anticlockwise moments about that point. This principle is used to analyze the equilibrium of objects under the influence of forces and torques. By considering the moments in opposite directions, the principle helps determine whether an object will remain in balance or rotate.

Submit
12. An electromagnetic relay can turn a small current on using a even smaller current

Explanation

An electromagnetic relay is a device that uses an electromagnet to control the flow of current in a circuit. When a small current flows through the coil of the relay, it generates a magnetic field that attracts a switch, allowing a larger current to flow through the circuit. This means that a small current can indeed control the switching of an even smaller current, making the statement "An electromagnetic relay can turn a small current on using an even smaller current" true.

Submit
13. Refraction is caused by :

Explanation

Refraction occurs when light enters a medium with a different speed, causing it to change direction. This change in speed is due to the change in the optical density of the medium, which alters the path of the light. When light travels from one medium to another, such as from air to water or from air to glass, the speed of light changes, leading to refraction. The change in angle or curvature of the medium does not directly cause refraction, but rather the change in speed of light is the primary factor.

Submit
14. A LDR has a high resitance in the dark.

Explanation

In a Light Dependent Resistor (LDR), the resistance decreases as the intensity of light increases. Therefore, in the absence of light (dark conditions), the LDR will have a high resistance. This is because the LDR's semiconductor material does not receive any photons to excite its electrons and allow the flow of current, resulting in a high resistance.

Submit
15. Power = 

Explanation

The correct answer is "work done / time taken". Power is defined as the amount of work done per unit time. This means that power is the rate at which work is done or the amount of work done in a given amount of time. Therefore, the equation "work done / time taken" accurately represents the concept of power.

Submit
16. Random motion of large visible particels, caused by smaller invisible ones is called:

Explanation

Brownian motion refers to the random movement of large visible particles, which is caused by the constant collisions with smaller invisible particles. This phenomenon was first observed by the botanist Robert Brown in 1827 when he noticed the erratic motion of pollen grains suspended in water. The motion is a result of the random thermal energy possessed by the smaller particles, such as molecules or atoms, which causes them to collide with the larger particles and impart momentum to them. This explanation of the correct answer suggests that Brownian motion is the term used to describe this random motion caused by smaller invisible particles.

Submit
17. Power = Energy / time

Explanation

The statement "Power = Energy / time" is true. Power is defined as the rate at which work is done or energy is transferred or converted. It is calculated by dividing the amount of energy by the time it takes to transfer or convert that energy. Therefore, the equation Power = Energy / time is correct and accurately represents the relationship between power, energy, and time.

Submit
18. Copper conducts electricity because it is a solid.

Explanation

The statement "Copper conducts electricity because it is a solid" is false. Copper conducts electricity not because it is a solid, but because it is a good conductor of electricity. The conductivity of a material is determined by its atomic structure and the ability of its electrons to move freely. Copper has a high number of free electrons that can easily move through the material, allowing it to conduct electricity efficiently.

Submit
19. P waves are longitudenal and arrive before S waves during an earthquake.

Explanation

P waves, also known as primary waves, are a type of seismic wave that travels through the Earth's interior. These waves are longitudinal, meaning that they cause particles to move in the same direction as the wave propagation. During an earthquake, P waves are the first to arrive at a seismograph station because they travel faster than S waves, which are transverse waves. Therefore, the statement that P waves arrive before S waves during an earthquake is true.

Submit
20. Newton's third law describes that:

Explanation

Newton's third law states that every action has an equal but opposite reaction. This means that for every force exerted on an object, there is an equal and opposite force exerted by the object. This law helps explain the concept of momentum and the interactions between objects. It highlights the interconnectedness of forces in nature and how they always occur in pairs.

Submit
21. Torque= force x perpendicular distance

Explanation

The statement "Torque = force x perpendicular distance" is true. Torque is a measure of the force that can cause an object to rotate around an axis. It is calculated by multiplying the force applied to the object by the perpendicular distance from the axis of rotation. This relationship is fundamental in understanding rotational motion and is used in various fields such as physics and engineering.

Submit
22. A barometer and a manometer use:

Explanation

A barometer and a manometer use mercury only because mercury is a dense liquid that is sensitive to changes in pressure. Both instruments measure pressure, with a barometer measuring atmospheric pressure and a manometer measuring pressure in a closed system. Mercury's high density allows it to accurately reflect changes in pressure, making it an ideal choice for these instruments. Chromium, boiling water, and cold water are not used in barometers or manometers.

Submit
23. In physics, the term "_____" refers to the resistance of any physical object to any change in its state of motion, including changes to its speed and direction.

Explanation

Inertia is a fundamental concept in physics that describes the tendency of an object to resist changes in its state of motion unless acted upon by an external force. It is a key principle of Newton's first law of motion, which states that an object at rest stays at rest and an object in motion stays in motion with the same speed and in the same direction unless acted upon by an unbalanced force. This property depends on the mass of the object; the greater the mass, the greater the inertia

Submit
24. Momentum = mass x _____________

Explanation

The equation for momentum is defined as the product of an object's mass and its velocity. This equation is derived from Newton's second law of motion, which states that the force acting on an object is equal to its mass multiplied by its acceleration. However, in this case, the question specifically asks for the missing factor in the equation for momentum, and velocity is the correct answer.

Submit
25. Speed is a : (tick two boxes)

Explanation

Speed is a scalar quantity because it only has magnitude and no direction. It represents the rate at which an object changes its position, regardless of the direction it is moving in. Therefore, it does not have a specific direction associated with it. Additionally, speed is a measure of how fast an object is moving, indicating its magnitude.

Submit
26. Convert: (i) 0 *C to Kelvin (ii) 341 K to *Celcius

Explanation

The correct answer for the first part of the question is 273K. This is because to convert from degrees Celsius to Kelvin, you need to add 273 to the Celsius temperature. Since the starting temperature is 0 degrees Celsius, adding 273 will give you 273K.

For the second part of the question, the correct answer is 68*C. To convert from Kelvin to degrees Celsius, you need to subtract 273 from the Kelvin temperature. Since the starting temperature is 341K, subtracting 273 will give you 68 degrees Celsius.

Submit
27. H = mL. The equation can be used to calculate the latent heat of fusion.

Explanation

The equation H = mL represents the relationship between the latent heat (H), mass (m), and specific latent heat (L) of a substance. This equation is used to calculate the amount of heat required to change a substance from a solid to a liquid state, which is known as the latent heat of fusion. Therefore, the statement "H = mL can be used to calculate the latent heat of fusion" is true.

Submit
28. Refractive index = speed of light in a vaccum / speed of light in a ___________.

Explanation

The refractive index is a measure of how much light slows down when it passes through a medium compared to its speed in a vacuum. It is calculated by dividing the speed of light in a vacuum by the speed of light in the medium. Therefore, the correct answer is "medium."

Submit
29. Match fingers to the components of the Fleming's left hand rule.
Submit
30. Specific heat capacity of water is 2400J/(kg*C).

Explanation

it is 4200

Submit
31. An off shore breeze relies on water having a smaller heat capacity than the land.

Explanation

This statement is false. An offshore breeze occurs when the wind blows from the land towards the water. It is caused by the temperature difference between the land and the water. During the day, the land heats up faster than the water, creating a lower pressure zone over the land. This causes the cooler air from the water to flow towards the land, creating an offshore breeze. Therefore, an offshore breeze relies on the water having a larger heat capacity than the land, not a smaller heat capacity.

Submit
32. Calculate the number of coils on the secondary coil of  transformers given that turns on primary coil = 240 and secondary voltage= 40V and primary voltage = 120V

Explanation

The number of coils on the secondary coil of a transformer can be calculated using the formula:

(number of turns on primary coil / primary voltage) * secondary voltage

In this case, the number of turns on the primary coil is given as 240, the primary voltage is 120V, and the secondary voltage is 40V. Plugging these values into the formula, we get:

(240 / 120) * 40 = 2 * 40 = 80

Therefore, the number of coils on the secondary coil is 80 turns.

Submit
33. A wave is travelling at 45m/s. The frequency of the wave is 3000Hz. Calulate its wavelength. (use correct units)

Explanation

The wavelength of a wave can be calculated by dividing the speed of the wave by its frequency. In this case, the wave is traveling at 45m/s and has a frequency of 3000Hz. By dividing the speed (45m/s) by the frequency (3000Hz), we get a wavelength of 0.015m. Therefore, the correct answer is 0.015 m.

Submit
34. An object moving in the orbit of earth, travels at constant velocity. Which law from the Newton's laws of motion correctly describes this.

Explanation

The first law of motion, also known as the law of inertia, states that an object at rest will stay at rest, and an object in motion will stay in motion with the same speed and direction, unless acted upon by an external force. In the case of an object moving in the orbit of Earth, it is constantly acted upon by the gravitational force of the Earth, which keeps it in orbit and maintains its constant velocity. Therefore, the first law of motion correctly describes this situation.

Submit
35. 3000 Gigawatts = __________ watts

Explanation

The answer 3 x 10^12 is correct because when converting from gigawatts to watts, you multiply by 10^9. So, 3000 gigawatts is equal to 3000 x 10^9 watts, which simplifies to 3 x 10^12 watts.

Submit
36. Efficieny = 

Explanation

The efficiency of a system is determined by the ratio of work done to the energy input. This means that the more work that is accomplished with a given amount of energy, the higher the efficiency. The other options, force x speed, work done / time taken, and power input / power output, are not correct explanations for efficiency.

Submit
37. Brushes are also used in motors to connect the power supply to the magnet.

Explanation

to connect to the coil, not the magnet

Submit
38. Pressure in liquids is given by : (only use symbols)

Explanation

The given correct answer states that the pressure in liquids is given by the equation P = pgh, where P represents pressure, p represents density, g represents acceleration due to gravity, and h represents the height or depth of the liquid. This equation is derived from the principle of hydrostatics, which states that the pressure in a liquid at rest increases with depth. Therefore, the pressure in liquids can be calculated by multiplying the density of the liquid, the acceleration due to gravity, and the height or depth of the liquid.

Submit
39. What is the equation for work done: so WORK DONE=

Explanation

The equation for work done is given by force multiplied by distance. This means that work done is equal to the product of the force applied on an object and the distance over which the force is applied. This equation quantifies the amount of energy transferred to or from an object as a result of the force exerted on it.

Submit
40. Acceleration = velocity / time

Explanation

The given equation, acceleration = velocity / time, is incorrect. The correct equation is acceleration = change in velocity / time. This is because acceleration is the rate at which velocity changes over time, not just the velocity divided by time. Therefore, the correct answer is False.

Submit
41. Charles law in symbols: p1V1/T1=p2V2/T2

Explanation

The statement "Charles law in symbols: p1V1/T1=p2V2/T2" is true. Charles's law states that the volume of a gas is directly proportional to its temperature, given that the pressure remains constant. The equation p1V1/T1=p2V2/T2 represents the relationship between the initial and final states of a gas undergoing a change in temperature and volume, while keeping the pressure constant. Therefore, the given statement is correct.

Submit
42. When going from a liquid to gas the following equation can be used to find out energy transffered. E = mc^2T. True or False?

Explanation

it is E= mc(delta)T

Submit
43. A soft iron core is used to keep a solenoid intact.

Explanation

A soft iron core is not used to keep a solenoid intact. Instead, it is used to increase the strength and intensity of the magnetic field produced by the solenoid. The soft iron core enhances the magnetic properties of the solenoid by providing a path of low reluctance for the magnetic flux, resulting in a stronger magnetic field.

Submit
44. Radiation is tranfer of heat enrgy in the form of __________ .

Explanation

Radiation is the transfer of heat energy in the form of waves. This means that heat energy can be transferred through the emission of electromagnetic waves, such as infrared radiation. These waves can travel through empty space and do not require a medium to transfer heat. Radiation is an important mechanism for heat transfer, as it allows heat to be transferred from a hot source to a cooler object without direct contact between them.

Submit
45. A thermistor has high resistance when its hot.

Explanation

A thermistor is a type of resistor that has a resistance that changes with temperature. In the case of a thermistor, it has a low resistance when it is hot, not a high resistance. This is because the resistance of a thermistor decreases as its temperature increases. Therefore, the statement that a thermistor has high resistance when it is hot is incorrect.

Submit
46. Which of the follwing is a law of reflection

Explanation

The correct answer is "angle of incidence= angle of reflection, incident angle, reflected angle and the normal all lie on the same plane." This is known as the law of reflection, which states that when a ray of light hits a surface and reflects, the angle of incidence (the angle between the incident ray and the normal to the surface) is equal to the angle of reflection (the angle between the reflected ray and the normal to the surface). Additionally, the incident angle, reflected angle, and the normal all lie on the same plane. This law is fundamental in understanding how light behaves when it interacts with surfaces.

Submit
47. The geographic North pole is the magnetic north as well.

Explanation

The statement is false because the geographic North pole and the magnetic north pole are not the same. The geographic North pole is the point where the Earth's axis of rotation intersects the Earth's surface, while the magnetic north pole is the point where the Earth's magnetic field points vertically downwards. These two poles are located at different points on the Earth's surface and can vary in their positions over time.

Submit
48. Electrical field lines always travel from -ve to +ve.

Explanation

The given statement is false. Electrical field lines always travel from positive to negative. According to convention, electric field lines represent the direction of the force experienced by a positive test charge. Since positive charges repel each other, the electric field lines originate from positive charges and terminate on negative charges. Therefore, the correct answer is false.

Submit
49. Law of Floatation: If an object is floating freely, the weight of fluid it displaces is equal to its ________a______. And if a material floats, its _____b______ must be equal to or less than that of the fluid supporting it.

Explanation

When an object is floating freely, it experiences an upward force called upthrust, which is equal to the weight of the fluid it displaces. This is known as the law of floatation. In order for a material to float, its density must be equal to or less than that of the fluid supporting it. Therefore, the correct answers are: a) weight, as the weight of the fluid displaced is equal to the upthrust, and b) density, as the density of the material must be equal to or less than that of the fluid.

Submit
50. A boat is travelling at 35 km/hr. Froce used to push the boat in the water in 350N. Calculate the useful power output of the boat.

Explanation

The useful power output of the boat can be calculated by multiplying the force used to push the boat in the water by the boat's velocity. In this case, the force is given as 350N and the velocity is given as 35 km/hr. First, we need to convert the velocity from km/hr to m/s by dividing it by 3.6. So, the velocity becomes 9.72 m/s. Then, we can calculate the useful power output by multiplying the force (350N) by the velocity (9.72 m/s), which gives us 3402W. However, since the answer options are in multiples of 10, the correct answer would be 10500W.

Submit
51. Mass of an object on Earth is 120kg. Calculate the weight of the person on the moon.[g(moon)= 1.6N/kg]. Remmember to use the correct units.

Explanation

The weight of an object is calculated by multiplying its mass by the acceleration due to gravity. On Earth, the acceleration due to gravity is approximately 9.8 m/s^2, but on the moon, it is 1.6 N/kg. Therefore, to calculate the weight of the person on the moon, we can multiply their mass (120 kg) by the acceleration due to gravity on the moon (1.6 N/kg). This gives us a weight of 192 N.

Submit
52. Calculate the crictical angle of a substance with refractive index 2.5. (answer to 1 d.p.) (do not use the degree sign)

Explanation

The critical angle of a substance can be calculated using the formula sin(critical angle) = 1/refractive index. In this case, the refractive index is given as 2.5. Plugging this value into the formula, we get sin(critical angle) = 1/2.5. Solving for the critical angle, we take the inverse sine of both sides, which gives us the critical angle as 23.6 degrees.

Submit
53. Which of the following are ferromagntic materials?

Explanation

Iron and nickel are ferromagnetic materials because they exhibit strong magnetic properties. They can be easily magnetized and retain their magnetization even after the external magnetic field is removed. Copper, on the other hand, is not a ferromagnetic material and does not possess these magnetic properties.

Submit
54. Match the component with its function
Submit
55. The substance above could be a ____________ .

Explanation

The substance mentioned in the question could be a diamond. This is because diamonds are known for their hardness and brilliance, making them one of the most valuable and sought-after gemstones. They have a distinct crystal structure and are composed of carbon atoms arranged in a specific way, giving them their unique properties.

Submit
56. ____________________ is used to visually represent a waveform on a screen

Explanation

An oscilloscope is a device that is used to visually represent a waveform on a screen. It is commonly used in electronics and electrical engineering to measure and analyze electrical signals. The oscilloscope displays the waveform as a graph, with the horizontal axis representing time and the vertical axis representing the amplitude of the signal. This allows engineers and technicians to observe and analyze the characteristics of the waveform, such as its frequency, amplitude, and shape.

Submit
57. Transistors can be used as ____________

Explanation

Transistors can be used as potential dividers. A potential divider is a circuit arrangement that divides the voltage across two or more resistors connected in series. Transistors can be configured in such a way that they act as variable resistors, allowing the voltage to be divided according to the desired ratio. This property makes transistors useful for applications such as volume control in audio systems or controlling the brightness of a light.

Submit
58. Which of the following will speed up the rate of a reaction?

Explanation

Increasing temperature and turning on a fan both increase the rate of a reaction. Increasing temperature provides more energy to the reactant molecules, leading to more frequent and energetic collisions, which increases the rate of reaction. Turning on a fan helps in increasing the rate of reaction by increasing the movement of air molecules around the reactants, which enhances the chances of collisions between reactant molecules and thus speeds up the reaction.

Submit
59. Which of the following information applies to generators

Explanation

Generators are devices that convert mechanical energy into electrical energy. They operate on AC voltage, meaning they produce alternating current. This is different from direct current (DC) which flows in only one direction. Generators use the principle of creating a magnetic field using a current, typically through the use of coils and magnets. This magnetic field induces a voltage in the coils, resulting in the generation of electricity. Generators that operate on AC voltage are also commonly referred to as alternators.

Submit
60. In a half wave rectification, a ___________ is used to convert ___ voltage to ___ .

Explanation

In a half wave rectification, a diode is used to convert AC voltage to DC. A diode allows current to flow in only one direction, blocking the negative half cycles of the AC voltage and allowing only the positive half cycles to pass through. This results in a rectified output voltage that has only the positive half cycles, effectively converting the AC voltage to DC voltage.

Submit
61. Which of the folling are NOT a feature/ example of transverse waves.

Explanation

Particles moving in the opposite direction to the direction of the wave is not a feature/example of transverse waves. In transverse waves, particles oscillate perpendicular to the direction of the wave. Sound waves, on the other hand, are longitudinal waves where particles move parallel to the direction of the wave. Therefore, sound waves cannot be considered as an example of transverse waves.

Submit
62. A car moving at constant velocity has which of the following forces acting on it?

Explanation

A car moving at constant velocity has three forces acting on it: thrust, gravity, and air resistance. Thrust is the force that propels the car forward, gravity is the force pulling the car downwards towards the ground, and air resistance is the force opposing the motion of the car as it moves through the air. These forces must be balanced in order for the car to maintain a constant velocity. Momentum, on the other hand, is not a force but a property of a moving object that depends on its mass and velocity.

Submit
63. Boyle law goes as: For a fixed mass of gas at constant temperature, the pressure is ___________ ___________ to the volume.

Explanation

According to Boyle's law, when the temperature of a fixed mass of gas is held constant, the pressure and volume of the gas are inversely proportional to each other. This means that as the volume of the gas increases, the pressure decreases, and vice versa. Similarly, if the volume decreases, the pressure increases. Therefore, the correct answer is "inversely, proportional."

Submit
64. Drake hears his echo from a wall standing 320m from him. Calculate time taken for him to hear his echo. (sound=330m/s) Round your answers to 2 d.p. ( use correct units)

Explanation

The time taken for Drake to hear his echo can be calculated using the formula: time = distance/speed. In this case, the distance is 320m and the speed of sound is 330m/s. Plugging these values into the formula, we get: time = 320m/330m/s = 0.969s. Rounded to 2 decimal places, the answer is 1.03s.

Submit
65. 14.5 A of current flows through a circuit with a power supply of 29V in 1.2s Calculate (i)Resistance: ______________ (ii)Charge: ____________________ (write out the correct symbols)

Explanation

The resistance can be calculated using Ohm's Law, which states that resistance (R) is equal to voltage (V) divided by current (I). In this case, the voltage is 29V and the current is 14.5A, so the resistance is 29V/14.5A = 2 ohms.

The charge can be calculated using the formula Q = I x t, where Q is the charge, I is the current, and t is the time. In this case, the current is 14.5A and the time is 1.2s, so the charge is 14.5A x 1.2s = 17.4 Coulombs.

Submit
66. Power=

Explanation

The correct answer is current^2 x resistance. This equation represents the power dissipated in a circuit, where the power is proportional to the square of the current flowing through the circuit and the resistance of the circuit. This relationship is derived from Ohm's Law (V = IR), where power can also be calculated as P = IV. By substituting V = IR into the power equation, we get P = I(IR) = I^2R, which matches the given answer.

Submit
67. Which of the follwing information is true?

Explanation

The given answer is correct because it accurately identifies the true statements from the options provided. It states that live wires carry AC voltage, which is true as live wires are responsible for carrying the alternating current in an electrical circuit. It also correctly states that the earth wire is a safety feature, as it provides a path for electrical current to safely dissipate into the ground in case of a fault. Additionally, it mentions that objects that are double insulated don't require an earth wire, which is true as double insulation provides an extra layer of protection against electric shock. Furthermore, it correctly states that RCDs and circuit breakers are used as safety features to protect against electrical faults. Finally, it correctly states the formula for energy transformation, which is energy transformed = power x time.

Submit
68. (use'^' for power of)Complete the kinematic equation : v^2=

Explanation

The correct answer is u^2 + 2*a*s. This is the correct form of the kinematic equation for calculating the final velocity squared (v^2) in terms of the initial velocity squared (u^2), acceleration (a), and displacement (s). The equation shows that the final velocity squared is equal to the sum of the initial velocity squared and twice the product of acceleration and displacement.

Submit
69. Which of the following is a feature of longitudenal waves?

Explanation

Longitudinal waves are characterized by the particles of the medium moving parallel to the direction of the wave. This movement results in the formation of compressions, where the particles are closer together, and rarefactions, where the particles are spread apart. Sound waves are an example of longitudinal waves, as they propagate through the compression and rarefaction of air particles. The statement "particles move to right angles at the direction of the wave" is incorrect, as it describes the motion of particles in transverse waves, not longitudinal waves.

Submit
70. Which of the following are features of electromagentic waves.

Explanation

Electromagnetic waves are all transverse waves, meaning that the oscillations occur perpendicular to the direction of wave propagation. None of the electromagnetic waves are visible to the human eye, as they fall outside the visible spectrum. Gamma rays have a bigger frequency compared to ultraviolet radiation, indicating that they have a higher energy and shorter wavelength. Most of the waves are emitted by charged particles oscillating, which is a characteristic of electromagnetic waves. X-rays can potentially cause cancer due to their high energy and ability to penetrate through tissues.

Submit
71. Short sighted people use ___________ lenses or ________________ .

Explanation

Short sighted people use progressive lenses or bifocal lenses because these types of lenses provide different focal lengths for near and distant vision. Progressive lenses have a gradual change in prescription strength from the top to the bottom of the lens, allowing for a smooth transition between different distances. Bifocal lenses have a distinct line separating the two different prescription strengths, with the top portion for distance vision and the bottom portion for near vision. Both types of lenses help correct the vision of short sighted individuals by providing clear vision at different distances.

Submit
View My Results

Quiz Review Timeline (Updated): Sep 2, 2024 +

Our quizzes are rigorously reviewed, monitored and continuously updated by our expert board to maintain accuracy, relevance, and timeliness.

  • Current Version
  • Sep 02, 2024
    Quiz Edited by
    ProProfs Editorial Team
  • Aug 17, 2012
    Quiz Created by
    Geniusasis
Cancel
  • All
    All (71)
  • Unanswered
    Unanswered ()
  • Answered
    Answered ()
Sound waves are caused by vibrations
Diaomond does not conduct electricity because it does not have any...
Force = ___________ x ________________
Any frequency over the limit of 20,000Hz is called an ultralsound...
An on shore breeze is caused because land warms faster and reatains...
Boyle's Law is symbols : p1V1=p2V2. True or False
Passing current through a wire produces a circular magnetic field,...
Photocopiers use the principle of electrostatic charges
Leaving air gaps makes a good insulator
Commutators are used in motos to the coil to change current direction...
Principle of moments says describes that: the sum of the...
An electromagnetic relay can turn a small current on using a even...
Refraction is caused by :
A LDR has a high resitance in the dark.
Power = 
Random motion of large visible particels, caused by smaller invisible...
Power = Energy / time
Copper conducts electricity because it is a solid.
P waves are longitudenal and arrive before S waves during an...
Newton's third law describes that:
Torque= force x perpendicular distance
A barometer and a manometer use:
In physics, the term "_____" refers to the resistance of any...
Momentum = mass x _____________
Speed is a : (tick two boxes)
Convert: (i) 0 *C to Kelvin (ii) 341 K to *Celcius
H = mL. The equation can be used to calculate the latent heat of...
Refractive index = speed of light in a vaccum / speed of light in a...
Match fingers to the components of the Fleming's left hand rule.
Specific heat capacity of water is 2400J/(kg*C).
An off shore breeze relies on water having a smaller heat capacity...
Calculate the number of coils on the secondary coil of...
A wave is travelling at 45m/s. The frequency of the wave is 3000Hz....
An object moving in the orbit of earth, travels at constant velocity....
3000 Gigawatts = __________ watts
Efficieny = 
Brushes are also used in motors to connect the power supply to the...
Pressure in liquids is given by : (only use symbols)
What is the equation for work done: so WORK DONE=
Acceleration = velocity / time
Charles law in symbols: p1V1/T1=p2V2/T2
When going from a liquid to gas the following equation can be used to...
A soft iron core is used to keep a solenoid intact.
Radiation is tranfer of heat enrgy in the form of __________ .
A thermistor has high resistance when its hot.
Which of the follwing is a law of reflection
The geographic North pole is the magnetic north as well.
Electrical field lines always travel from -ve to +ve.
Law of Floatation: If an object is floating freely, the weight of...
A boat is travelling at 35 km/hr. Froce used to push the boat in the...
Mass of an object on Earth is 120kg. Calculate the weight of the...
Calculate the crictical angle of a substance with refractive index...
Which of the following are ferromagntic materials?
Match the component with its function
The substance above could be a ____________ .
____________________ is used to visually represent a waveform on a...
Transistors can be used as ____________
Which of the following will speed up the rate of a reaction?
Which of the following information applies to generators
In a half wave rectification, a ___________ is used to convert ___...
Which of the folling are NOT a feature/ example of transverse waves.
A car moving at constant velocity has which of the following forces...
Boyle law goes as: For a fixed mass of gas at constant temperature,...
Drake hears his echo from a wall standing 320m from him. Calculate...
14.5 A of current flows through a circuit with a power supply of 29V...
Power=
Which of the follwing information is true?
(use'^' for power of)Complete the kinematic equation : v^2=
Which of the following is a feature of longitudenal waves?
Which of the following are features of electromagentic waves.
Short sighted people use ___________ lenses or ________________ .
Alert!

Advertisement