Conservation of Energy COPY

Question 1

What is energy?

Answer 1

The ability to do work. The unit for energy is the Joule.

Question 2

What is work?

Answer 2

A measurement of force x distance. Work is a transfer of energy. The unit is Joules or Newton-meters.

Question 3

What is Power?

Answer 3

The rate of doing work. The unit for power is Watts.

Question 4

Why is the work the same but the power different when a person runs up the stairs or walks up the stairs?

Answer 4

The work is the same because the person moves his/her weight up the same distance from the ground to the next level. The power is different: more power needed to run up the stairs because the work is done in less time.

Question 5

What is kinetic energy?

Answer 5

Energy of Motion

Question 6

What is electrical energy?

Answer 6

Energy of moving electrons across a potential difference. Electrical energy is a form of kinetic energy.

Question 7

What is radiant (light) energy?

Answer 7

Energy that travels by waves, especially electromagnetic energy. Radiant energy is a form of kinetic energy

Question 8

What is gravitational kinetic energy?

Answer 8

Energy of an object moving because of a gravitational force.

Question 9

What is sound energy?

Answer 9

Energy of a vibrating substance. Sound energy is a form of kinetic energy.

Question 10

What is mechanical energy?

Answer 10

Energy of moving parts. Mechanical energy is a form of kinetic energy.
Some sources use the term mechanical energy for total energy (kinetic + potential)

Question 11

What is potential energy?

Answer 11

Stored energy or energy of position

Question 12

What is gravitational potential energy?

Answer 12

Energy stored in an object that is above a reference level.

Question 13

What is chemical energy?

Answer 13

Energy stored in the bonds of substances. Chemical energy is a form of potential energy.

Question 14

What are some examples of chemical energy?

Answer 14

Fossil fuels, biomass, and food.

Question 15

What is elastic energy?

Answer 15

The energy stored in an object under stress. Elastic is a form of potential energy.

Question 16

What are some examples of elastic energy?

Answer 16

Compressed springs, stretched or twisted rubber bands, and rocks along a fault before an earthquake.

Question 17

What is the Law of Conservation of Energy?

Answer 17

The total energy of a system does not change; instead, energy can change from one form to another.

Question 18

What is the Work-Energy theorem?

Answer 18

Work done on a system will change the energy in the system.
For example, when a seagull lifts a oyster shell from the sea up into the air, the seagull applies a force to move the oyster a distance (work). The oyster gains potential energy because it is now at a height above sea level.

Question 19

How can the Law of Conservation of Energy be used to calculate changes between potential and kinetic energy?

Answer 19

KE1 + PE1 = KE2 + PE2 In a system, total energy remains constant as energy transfers between potential and kinetic energy.

Question 20

How can you determine whether work was done on an object?

Answer 20

Work is done when a force acts on an object and the object moves in the direction that the force acts. Work is not done if the object does not move. Work is not done if the object remains in motion without an unbalanced force acting on it.

Question 21

What is nuclear energy?

Answer 21

The energy stored in the nucleus of an atom. Examples of the use of this energy is nuclear fission power plants and nuclear fusion in the cores of stars. Nuclear energy is a form of potential energy.

Question 22

Why is kinetic energy a positive value?

Answer 22

Whether the velocity is positive or negative, squaring the value of velocity will produce a positive number.

Question 23

Can potential energy be negative?

Answer 23

Potential energy could have a negative value if the object is in a position below the reference level.

Question 24

What is thermal energy?

Answer 24

The energy of moving atoms or molecules in a substance. The transfer of thermal energy is called heat. Thermal energy is a form of kinetic energy.