Conservation Of Energy Quiz Questions And Answers

1. The law of conservation of energy states...

It is important for any civilization to conserve its energy.

Energy that is not actively conserved will be lost forever.

Energy cannot be created or destroyed, only transformed.

All of these

The correct answer is "energy cannot be created or destroyed, only transformed." This statement is a fundamental principle in physics known as the law of conservation of energy. It states that the total amount of energy in a closed system remains constant over time. Energy can change from one form to another, such as potential energy to kinetic energy, but the total amount of energy remains constant. This principle is widely applicable and helps us understand various phenomena in the universe.

Explanation

The correct answer is "energy cannot be created or destroyed, only transformed." This statement is a fundamental principle in physics known as the law of conservation of energy. It states that the total amount of energy in a closed system remains constant over time. Energy can change from one form to another, such as potential energy to kinetic energy, but the total amount of energy remains constant. This principle is widely applicable and helps us understand various phenomena in the universe.

2. The unit of energy is

Newton

Joule

Ampere

Watt

The unit of energy is Joule. Joule is the standard unit of energy in the International System of Units (SI). It is defined as the amount of work done when a force of one newton is applied over a distance of one meter. Energy is a fundamental physical quantity that is used to measure the capacity of a system to do work or produce heat.

Explanation

The unit of energy is Joule. Joule is the standard unit of energy in the International System of Units (SI). It is defined as the amount of work done when a force of one newton is applied over a distance of one meter. Energy is a fundamental physical quantity that is used to measure the capacity of a system to do work or produce heat.

3. I stretch a rubberband and fling it at across the room. When does the rubber band have energy?

Only when its flying across the room.

Only when it was stretched tight.

Both when its stretched tight and when its flying across the room.

There is not enough information to answer this question.

When you stretch a rubberband, you are using your own energy to give the rubberband potential energy. When you release the band, its energy gets transformed into moving energy (kinetic energy).

Explanation

When you stretch a rubberband, you are using your own energy to give the rubberband potential energy. When you release the band, its energy gets transformed into moving energy (kinetic energy).

4. Describe your energy at the top of a roller coaster hill, just before you start moving into the big drop. You are currently perfectly still (aside from the screaming).

Because you aren't moving, you have no energy.

You have potential energy.

You have kinetic energy.

You have both kinetic energy and potential energy.

Kinetic energy comes from motion.

Explanation

Kinetic energy comes from motion.

5. Suppose, you played with a generator (this was the gun-looking object with the crank on one end) yesterday. Why were you able to light up the lightbulb when you turned the crank?

The magnet inside made the energy and passed it to the light bulb.

The energy you used to turn the crank was converted into electricity.

By turning the crank, you turned on a battery inside the generator.

All of these

When you turned the crank of the generator, the energy you exerted was converted into electricity. This conversion is made possible by the internal mechanisms of the generator, which typically involve a magnet and coils of wire. As you rotate the crank, the magnet spins inside the generator, inducing a current in the wire coils through electromagnetic induction. This current is then used to power the lightbulb, allowing it to light up. Therefore, the correct answer is that the energy from your physical effort was transformed into electrical energy.

Explanation

When you turned the crank of the generator, the energy you exerted was converted into electricity. This conversion is made possible by the internal mechanisms of the generator, which typically involve a magnet and coils of wire. As you rotate the crank, the magnet spins inside the generator, inducing a current in the wire coils through electromagnetic induction. This current is then used to power the lightbulb, allowing it to light up. Therefore, the correct answer is that the energy from your physical effort was transformed into electrical energy.

6. Solar panels can generate solar energy.

True

False

Solar panels are specifically designed to convert sunlight into electrical energy through the photovoltaic effect. They do generate solar energy by capturing sunlight and transforming it into usable electricity, which is a form of solar energy. Therefore, the correct answer is true.

Explanation

Solar panels are specifically designed to convert sunlight into electrical energy through the photovoltaic effect. They do generate solar energy by capturing sunlight and transforming it into usable electricity, which is a form of solar energy. Therefore, the correct answer is true.

7. Conservation of energy applies only to isolated systems.

True

False

The statement is true because the conservation of energy principle states that energy cannot be created or destroyed, only transferred or transformed. This principle applies specifically to isolated systems, which are systems that do not interact with their surroundings and do not exchange energy or matter with the external environment. In isolated systems, the total amount of energy remains constant over time. However, in non-isolated systems, energy can be lost or gained through interactions with the surroundings, violating the principle of conservation of energy. Therefore, conservation of energy only applies to isolated systems.

Explanation

The statement is true because the conservation of energy principle states that energy cannot be created or destroyed, only transferred or transformed. This principle applies specifically to isolated systems, which are systems that do not interact with their surroundings and do not exchange energy or matter with the external environment. In isolated systems, the total amount of energy remains constant over time. However, in non-isolated systems, energy can be lost or gained through interactions with the surroundings, violating the principle of conservation of energy. Therefore, conservation of energy only applies to isolated systems.

8. The heat added to or removed from the system is represented by using which alphabet?

U

W

Q

H

The alphabet used to represent the heat added to or removed from the system is Q. In thermodynamics, Q represents the heat transfer, which can be positive when heat is added to the system or negative when heat is removed from the system. The other options, U, W, and H, are commonly used to represent internal energy, work, and enthalpy respectively, but not specifically heat transfer.

Explanation

The alphabet used to represent the heat added to or removed from the system is Q. In thermodynamics, Q represents the heat transfer, which can be positive when heat is added to the system or negative when heat is removed from the system. The other options, U, W, and H, are commonly used to represent internal energy, work, and enthalpy respectively, but not specifically heat transfer.

9. Where does electricity in your house come from (the type that comes on when you flip a switch)?

Coal and oil are burned to heat up wires, which makes energy flow through wires.

Humans mine rocks that are naturally magnetic and electric. These are made into large batteries.

Humans heat up water and create steam in order to spin magnets near wires.

Earth's magnetic field is used to create electricity.

No one knows for sure where electricity comes from.

The correct answer is that humans heat up water and create steam in order to spin magnets near wires. This is a description of how electricity is generated in a power plant. The heat from burning coal or oil is used to heat up water and create steam, which in turn spins turbines that are connected to magnets. The spinning magnets generate electricity that is then transmitted through wires to our homes.

Explanation

The correct answer is that humans heat up water and create steam in order to spin magnets near wires. This is a description of how electricity is generated in a power plant. The heat from burning coal or oil is used to heat up water and create steam, which in turn spins turbines that are connected to magnets. The spinning magnets generate electricity that is then transmitted through wires to our homes.

10. Who proposed first, "Energy can neither be created nor be destroyed."?

Émilie du Châtelet

Julius Robert von Mayer

James Prescott Joule

Hermann Ludwig Ferdinand

Émilie du Châtelet proposed the idea that energy cannot be created or destroyed. This concept is known as the law of conservation of energy and is a fundamental principle in physics. It states that the total amount of energy in a closed system remains constant over time, although it can change forms. This idea was later developed and expanded upon by other scientists, including Julius Robert von Mayer, James Prescott Joule, and Hermann Ludwig Ferdinand. However, Émilie du Châtelet is credited with being one of the first to propose this concept.

Explanation

Émilie du Châtelet proposed the idea that energy cannot be created or destroyed. This concept is known as the law of conservation of energy and is a fundamental principle in physics. It states that the total amount of energy in a closed system remains constant over time, although it can change forms. This idea was later developed and expanded upon by other scientists, including Julius Robert von Mayer, James Prescott Joule, and Hermann Ludwig Ferdinand. However, Émilie du Châtelet is credited with being one of the first to propose this concept.