Evaluation: Conservation of Mechanical Energy (Grade 9-STE)

What does the law of conservation of mechanical energy state?

• • Potential energy is always equal to kinetic energy

• • Potential energy is always converted to kinetic energy

• • There is always some energy lost as heat

• • For any system the total amount of mechanical energy remains the same

Which best describes potential energy?

• • Energy of motion

• • Energy as heat

• • Stored energy

• • Energy that is doing work

Which of the following happens to the energy of a coconut that falls freely?

• • Loses potential and gains kinetic energy.

• • Loses both potential and gains kinetic energy.

• • Gains potential and loses kinetic energy.

• • Gains both potential and kinetic energy.

Which of the following statements is true?

• • The principle of the conservation of mechanical energy states that the total mechanical energy in a system remains constant as long as the only forces acting are conservative forces.

• • Total energy is conserved for every system of particles on which there is an external work done.

• • Some kinetic energy of an object will not be transformed into potential energy and other forms of energy.

• • Total energy is not conserved for every system of particles.

The total mechanical energy of the object at the highest point compared to its total mechanical energy at the lowest point is

• • lesser

• • greater

• • equal

• • not related

Mechanical energy is the sum of Potential and Kinetic Energy.

• True

• False

Kinetic and Potential energy are the two types of Mechanical Energy.

• True

• False

Hydropower Energy uses kinetic and potential energy to generate electricity.

• True

• False

Kinetic Energy is known as “energy in moving matter”

• True

• False

Kinetic energy cannot to transformed or converted to potential energy.

• True

• False