Topic 1 - Energy

Question 1

What is energy?

Answer 1

The ability to do work or cause change.

Question 2

What is the unit of energy?

Answer 2

Joule (J).

Question 3

True or False: Energy can be created or destroyed.

Answer 3

False.

Question 4

What is the law of conservation of energy?

Answer 4

Energy cannot be created or destroyed; it can only be transformed from one form to another.

Question 5

What is kinetic energy?

Answer 5

The energy an object has due to its motion.

Question 6

What is the formula for kinetic energy?

Answer 6

KE = 0.5 * m * v^2, where m is mass and v is velocity.

Question 7

What is potential energy?

Answer 7

The energy stored in an object due to its position or state.

Question 8

What is gravitational potential energy?

Answer 8

The potential energy an object has due to its height above the ground.

Question 9

What is the formula for gravitational potential energy?

Answer 9

PE = m * g * h, where m is mass, g is gravitational field strength, and h is height.

Question 10

Fill in the blank: The total energy in a closed system remains _______.

Answer 10

constant.

Question 11

What is thermal energy?

Answer 11

The energy that comes from the temperature of matter.

Question 12

What is the main source of energy on Earth?

Answer 12

The Sun.

Question 13

What is renewable energy?

Answer 13

Energy from sources that are naturally replenished, such as solar or wind energy.

Question 14

What is non-renewable energy?

Answer 14

Energy from sources that cannot be replenished in a short time, such as fossil fuels.

Question 15

True or False: All forms of energy can be converted to other forms.

Answer 15

True.

Question 16

What is mechanical energy?

Answer 16

The sum of kinetic and potential energy in an object.

Question 17

What does the term ‘work’ mean in physics?

Answer 17

The transfer of energy that occurs when a force is applied over a distance.

Question 18

What is the formula for work?

Answer 18

W = F * d, where W is work, F is force, and d is distance.

Question 19

Fill in the blank: Power is the rate of _______.

Answer 19

doing work.

Question 20

What is the unit of power?

Answer 20

Watt (W).

Question 21

What is the formula for power?

Answer 21

P = W / t, where P is power, W is work, and t is time.

Question 22

What is energy transfer?

Answer 22

The movement of energy from one place or object to another.

Question 23

What is efficiency?

Answer 23

The ratio of useful energy output to total energy input, usually expressed as a percentage.

Question 24

How can efficiency be calculated?

Answer 24

Efficiency = (Useful energy output / Total energy input) * 100.

Question 25

What is fossil fuel?

Answer 25

A natural fuel formed from the remains of ancient plants and animals.

Question 26

What is a solar cell?

Answer 26

A device that converts sunlight directly into electricity.

Question 27

What is biomass energy?

Answer 27

Energy produced from organic materials, such as plant and animal waste.

Question 28

What is hydroelectric power?

Answer 28

Electricity generated by using water flow to turn turbines.

Question 29

What is wind energy?

Answer 29

Energy obtained from the movement of air.

Question 30

What is geothermal energy?

Answer 30

Energy derived from the heat stored beneath the Earth's surface.

Question 31

What is nuclear energy?

Answer 31

Energy released during nuclear fission or fusion.

Question 32

What is a heat engine?

Answer 32

A machine that converts thermal energy into mechanical work.

Question 33

What does 'thermal conductivity' refer to?

Answer 33

The ability of a material to conduct heat.

Question 34

What is conduction?

Answer 34

The transfer of heat through a material without the movement of the material itself.

Question 35

What is convection?

Answer 35

The transfer of heat by the movement of fluids (liquids and gases).

Question 36

What is radiation?

Answer 36

The transfer of energy through electromagnetic waves.

Question 37

What is a closed system?

Answer 37

A physical system that does not exchange matter with its surroundings.

Question 38

What is the difference between heat and temperature?

Answer 38

Heat is the energy transferred due to temperature difference, while temperature is a measure of the average kinetic energy of particles.

Question 39

What is specific heat capacity?

Answer 39

The amount of energy required to raise the temperature of 1 kg of a substance by 1 degree Celsius.

Question 40

What is the formula for specific heat capacity?

Answer 40

Q = m * c * ΔT, where Q is heat energy, m is mass, c is specific heat capacity, and ΔT is the change in temperature.

Question 41

What is a renewable resource?

Answer 41

A resource that can be replenished naturally over time.

Question 42

What is a non-renewable resource?

Answer 42

A resource that cannot be replaced once it is used up.

Question 43

What is energy efficiency?

Answer 43

The goal of reducing the amount of energy required to provide the same level of energy service.

Question 44

What is an energy transfer diagram?

Answer 44

A visual representation showing how energy is transferred from one form to another.

Question 45

True or False: All energy transformations are 100% efficient.

Answer 45

False.