Types of Energy and Conservation

What is mechanical energy?

• It is what metal creates when heated.
• All potential and kinetic energy in a system.
• It is motion of all matter.
• Energy of momentum.

An object is speeding up when: (Choose All That Apply)

• it is gaining kinetic energy.

• it is losing kinetic energy.

• it is gaining gravitational potential energy.

• it is losing gravitational potential energy.

Explain what happens to the potential energy of a rock as it falls off the side of a cliff.

• The kinetic energy decreases as the potential energy increases.
• The kinetic energy decreases as the potential energy decreases.
• The potential energy decreases as the kinetic energy increases.
• The potential energy decreases as the kinetic energy decreases. 

If a pendulum has 20 J of potential energy at point 1, how much kinetic energy will it have a point 3?

• 0 J

• 10 J

• 20 J

• 30 J

If a pendulum has 30 J of kinetic energy at point 3, how much potential energy will it have a point 3?

• 0 J

• 10 J

• 20 J

• 30 J

If a ball tossed into the air has a maximum gravitational potential energy of 5.75 joules, what is its maximum kinetic energy in the same toss?

• 5.75 joules

• 11.14 joules

• 2.88 joules

• 7.93 joules

Where is the car moving fastest?

• A

• B

• C

• D

Which of the following is NOT a kind of energy that makes up mechanical energy in a system?

• gravitational potential energy

• kinetic energy

• elastic potential energy

• thermal energy

Which of the following is FALSE according to the law of conservation of energy?

• total mechanical energy in a system is conserved

• the amount of energy in a system always changes

• if you add up the kinetic and potential energies for a system at any given time, the total energy will always be the same value

• Energy in a system can be transformed into different types of energy but it can never be destroyed

Which of the following is INCORRECTLY matches the type of energy with its description?

• Kinetic Energy - energy of motion

• Gravitational Potential - energy due to position

• Elastic Potential - energy stored in a spring

• Mechanical Energy - energy in the form of heat