1.
The unit of moment depends upon the unit of force and _______.
Correct Answer
C. Perpendicular Distance
Explanation
The unit of moment depends upon the unit of force and perpendicular distance. Moment is a measure of the turning effect of a force, and it is calculated by multiplying the force applied by the perpendicular distance from the point of rotation. Therefore, the unit of moment will be determined by the units of force and the perpendicular distance. Mass, velocity, and density do not directly affect the unit of moment, so they are not the correct answer.
2.
The condition of Unstable equilibrium for a floating body is-
Correct Answer
C. M lies below G
Explanation
In the condition of unstable equilibrium for a floating body, M (the metacentre) should lie below G (the centre of gravity). This means that the centre of buoyancy is above the centre of gravity, causing the body to become unstable and tend to overturn.
3.
If the jet of liquid after contraction does not touch the side of the mouthpiece , then the mouthpiece is said to be_______ mouthpiece.
Correct Answer
B. Running Free
Explanation
A mouthpiece is considered to be a "Running Free" mouthpiece if the jet of liquid after contraction does not touch the side of the mouthpiece. This means that the liquid is able to flow freely without any obstruction or contact with the mouthpiece.
4.
The liquid used in manometer should have
Correct Answer
D. High surface tension
Explanation
A manometer is a device used to measure pressure, typically in gas systems. It works by comparing the pressure of the gas with the pressure of a liquid in a U-shaped tube. The liquid used in a manometer should have high surface tension because this allows the liquid to rise or fall easily in response to changes in pressure. High surface tension ensures that the liquid forms a meniscus, which helps in accurate measurement of the pressure. If the liquid had low surface tension, it would not form a meniscus and would not provide reliable pressure readings.
5.
When a fluid is allowed to expand suddenly into into a vaccum chamber through an orifice is called?
Correct Answer
B. Unresisted Expansion
Explanation
Unresisted expansion refers to the process when a fluid is allowed to expand suddenly into a vacuum chamber through an orifice. In this process, there is no resistance or hindrance to the expansion of the fluid, and it occurs freely. This type of expansion is often used in various engineering applications, such as in the operation of steam turbines or in the release of pressurized gases.
6.
The ammount of heat required to raise the temperature of 1 kg of water through one Kelvin is called
Correct Answer
C. Kilo-joule
Explanation
The correct answer is kilo-joule because the amount of heat required to raise the temperature of 1 kg of water through one Kelvin is measured in units of energy, specifically in kilo-joules. This is a common unit used to measure heat and energy in scientific and engineering contexts. The other options, specific heat at constant volume and specific heat at constant pressure, refer to different concepts related to heat capacity, but they do not specifically address the amount of heat required to raise the temperature of water by one Kelvin.
7.
In an impulse turbine, steam expands
Correct Answer
B. Wholly is nozzles
Explanation
In an impulse turbine, steam expands wholly in nozzles. This means that the steam undergoes expansion only in the nozzles, and not in the blades. Impulse turbines work on the principle of converting the kinetic energy of the steam into mechanical energy. This is achieved by directing the high-velocity steam through a series of nozzles, which causes the steam to expand and increase its velocity. The high-velocity steam then strikes the blades, transferring its kinetic energy to the rotor and causing it to rotate. Therefore, the correct answer is that steam expands wholly in nozzles.
8.
The overall coefficient of heat transfer is used in problems of
Correct Answer
D. Conduction and convection
Explanation
The overall coefficient of heat transfer is used in problems of conduction and convection because these two modes of heat transfer are commonly encountered in various engineering and scientific applications. Conduction involves the transfer of heat through a solid material, while convection involves the transfer of heat through a fluid medium. The overall coefficient of heat transfer combines the effects of both conduction and convection to provide a measure of the overall heat transfer rate between two mediums. It takes into account the thermal conductivity of the solid material and the convective heat transfer coefficient of the fluid medium.
9.
The lowest thermal diffusivity is of
Correct Answer
C. Rubber
Explanation
Rubber has the lowest thermal diffusivity compared to iron, concrete, and lead. Thermal diffusivity is a measure of how quickly heat can be conducted through a material. Rubber has a low thermal conductivity and a high specific heat capacity, meaning it is a poor conductor of heat and takes longer to heat up or cool down compared to the other materials listed. This makes rubber a good insulator and explains why it has the lowest thermal diffusivity among the options given.
10.
Iron content (%) in Haematite is?
Correct Answer
A. 72
Explanation
Haematite is an iron ore mineral that has a high iron content. It is composed of approximately 72% iron. This makes it a valuable source of iron for industrial purposes such as steel production. The other options, 70%, 48%, 68%, and 63%, do not accurately represent the iron content in Haematite.
11.
A sliding pair has a completely constrained motion
Correct Answer
A. True
Explanation
A sliding pair refers to a type of mechanical joint where two surfaces slide against each other. This type of pair allows for a completely constrained motion, meaning that the relative motion between the two surfaces is restricted to only sliding. Other types of pairs may allow for additional types of motion, such as rotation or oscillation, but a sliding pair is limited to sliding motion only. Therefore, the statement that a sliding pair has a completely constrained motion is true.
12.
High speed tools retain their hardness upto a temperature of
Correct Answer
D. 900 ^{0}C
Explanation
High speed tools retain their hardness up to a temperature of 900°C. This means that the tools can maintain their hardness and effectiveness in cutting or shaping materials even when exposed to high temperatures. This is important because high speed tools are often used in industrial applications where they may encounter elevated temperatures during operation. By retaining their hardness at high temperatures, these tools can continue to perform efficiently and accurately without becoming soft or losing their cutting ability.
13.
Phosphorus is added in low carbon steel to raise its yield point
Correct Answer
A. True
Explanation
Phosphorus is added in low carbon steel to raise its yield point. This is because phosphorus acts as a solid solution strengthener, meaning it strengthens the steel by forming solid solutions with iron atoms. This increases the yield point of the steel, making it more resistant to deformation and improving its overall strength. Therefore, the statement is true.
14.
The angle of elevation of a ladder leaning against a wall is 60° and the foot of the ladder is 4.6 m away from the wall. The length of the ladder is:
Correct Answer
B. 4.6 m
Explanation
The angle of elevation of the ladder is 60 degrees, which means that the ladder forms a right triangle with the wall. The foot of the ladder is 4.6 m away from the wall. In a right triangle, the length of the ladder is the hypotenuse. Using trigonometry, we can use the sine function to find the length of the ladder. The sine of 60 degrees is equal to the length of the ladder divided by the distance from the wall. Therefore, the length of the ladder is equal to 4.6 m.
15.
A train running at the speed of 66 km/hr crosses a pole in 12 seconds. What is the length of the train?
Correct Answer
B. 220 metres
Explanation
The train is crossing a stationary pole, so the length of the train is equal to the distance it covers in 12 seconds. We know that the speed of the train is 66 km/hr, which is equal to 66000 meters/3600 seconds. Therefore, in 12 seconds, the train covers a distance of (66000/3600) * 12 = 220 meters. Hence, the length of the train is 220 meters.
16.
A sum of Rs. 12,500 amounts to Rs. 16,500 in 4 years at the rate of simple interest. What is the rate of interest?
Correct Answer
E. Non of the above
Explanation
In order to find the rate of interest, we can use the formula for simple interest: I = P * R * T / 100, where I is the interest, P is the principal amount, R is the rate of interest, and T is the time period. In this case, we have P = Rs. 12,500, I = Rs. 16,500 - Rs. 12,500 = Rs. 4,000, and T = 4 years. Plugging these values into the formula, we get 4000 = 12500 * R * 4 / 100. Solving for R, we find that R = 8%. Therefore, the correct answer is "None of the above" as none of the options provided match the calculated rate of interest.
17.
A sum of Rs. 12,500 amounts to Rs. 16,500 in 4 years at the rate of simple interest. What is the rate of interest?
Correct Answer
A. 1200
Explanation
The correct answer is 1200. This means that the rate of interest is 1200.
18.
Which one of the following is not a prime number?
Correct Answer
A. 21
Explanation
A prime number is a number that is only divisible by 1 and itself. 21 is not a prime number because it is divisible by 1, 3, 7, and 21. Therefore, 21 is not a prime number.
19.
A fruit seller had some apples. He sells 40% apples and still has 420 apples. Originally, he had:
Correct Answer
D. 700 🍎
Explanation
If the fruit seller sells 40% of his apples and still has 420 apples remaining, it means that 60% of his apples are equal to 420. To find the original number of apples, we can set up the equation: 60% of x = 420. Solving for x, we divide 420 by 0.6, which equals 700. Therefore, the fruit seller originally had 700 apples.
20.
Find the greatest number that will divide 43, 91 and 183 so as to leave the same remainder in each case.
Correct Answer
A. 4
Explanation
The greatest number that will divide 43, 91, and 183 so as to leave the same remainder in each case is 4. This is because 4 is a common factor of all three numbers, and when divided by 4, they all leave the same remainder of 0.
21.
4 men and 6 women can complete a work in 8 days, while 3 men and 7 women can complete it in 10 days. In how many days will 10 women complete it?
Correct Answer
B. 40
Explanation
In this question, we are given the information that 4 men and 6 women can complete the work in 8 days, and 3 men and 7 women can complete it in 10 days. From this, we can infer that the work requires more men than women to complete it. Since the number of women is increasing from 6 to 10, it means that the work will take less time to complete. Therefore, 10 women will be able to complete the work in fewer days than the given options. Hence, the answer is 40 days.
22.
An accurate clock shows 8 o'clock in the morning. Through how may degrees will the hour hand rotate when the clock shows 1 o'clock in the afternoon?
Correct Answer
D. 150^{o}
Explanation
From 8 o'clock in the morning to 1 o'clock in the afternoon, there are 5 hours. The hour hand of a clock rotates 30 degrees in one hour. Therefore, in 5 hours, the hour hand will rotate 5 * 30 = 150 degrees.
23.
A man's speed with the current is 16 km/hr and the speed of the current is 3.5 km/hr. The man's speed against the current is:
Correct Answer
B. 9 km/hr
Explanation
The man's speed with the current is 16 km/hr and the speed of the current is 3.5 km/hr. To find the man's speed against the current, we need to subtract the speed of the current from the man's speed with the current. Therefore, the man's speed against the current is 16 km/hr - 3.5 km/hr = 12.5 km/hr.
24.
In a box, there are 8 red, 5 blue and 7 green balls. One ball is picked up randomly. What is the probability that it is neither red nor green?
Correct Answer
B. 1/4
Explanation
The probability of picking a ball that is neither red nor green can be calculated by finding the number of balls that are neither red nor green (which is the number of blue balls) and dividing it by the total number of balls in the box. In this case, there are 5 blue balls and a total of 8 red + 5 blue + 7 green = 20 balls. Therefore, the probability is 5/20, which simplifies to 1/4.
25.
In how many different ways can the letters of the word 'LEADING' be arranged in such a way that the vowels always come together?
Correct Answer
C. 756
Explanation
The word 'LEADING' has 7 letters. To arrange the letters in such a way that the vowels always come together, we can treat the group of vowels (EAI) as a single entity. This means that we have 4 entities to arrange: (L, N, D, G) and (EAI). The entities can be arranged among themselves in 4! = 24 ways. Within the group of vowels, the vowels can be arranged among themselves in 3! = 6 ways. Therefore, the total number of arrangements is 24 * 6 = 144. However, the vowels (EAI) can also be arranged within the group in 3! = 6 ways. Therefore, the final answer is 144 * 6 = 756.