Energy

Student Name

Which of the following is NOT an energy store?

• A) Kinetic
• B) Gravitational potential
• C) Sound
• D) Thermal

What is the principle of conservation of energy?

• A) Energy can be created but not destroyed
• B) Energy can be destroyed but not created
• C) Energy cannot be created or destroyed, only transferred
• D) Energy is always lost in all processes

What is the unit of energy?

• A) Watt
• B) Newton
• C) Joule
• D) Pascal

A ball of mass 2 kg is lifted to a height of 5 m. What is the gravitational potential energy gained? (g = 10 N/kg)

• A) 10 J
• B) 50 J
• C) 100 J
• D) 200 J

Which device is designed to convert chemical energy into electrical energy?

• A) Electric motor
• B) Solar cell
• C) Battery
• D) Generator

What does efficiency measure?

• A) The total energy used
• B) The useful energy output compared to total energy input
• C) The amount of energy wasted
• D) The speed of energy transfer

The Sankey diagram shows:

• A) Only useful energy output
• B) Only wasted energy
• C) Both useful and wasted energy
• D) The total time taken in a process

What is the equation for kinetic energy?

• KE=1/2mv^2
• KE=mgh
• KE=Fd
• KE=P x t

Which of the following increases the efficiency of a machine?

• A) Increasing friction
• B) Lubrication to reduce friction
• C) Adding weight
• D) Increasing wasted heat energy