Unit 2

Engineers are building a dam in a river valley. Once the dam is built, a reservoir will develop.

• to convert electrical energy into potential energy

• to convert potential energy into electrical energy

• to convert electromagnetic energy into kinetic energy

• to convert kinetic energy into gravitational energy

Angela has a toy made out of a coil of wire. She places the toy at the top of some stairs. The toy can travel down each step, end-over-end.

Which type of energy does the toy have when it is placed at the top of the stairs?

• electric

• kinetic

• magnetic

• potential

The picture shows a pulley system with three platforms.

Which would MOST likely happen if the mass on Platform 2 was removed?

• Platforms 1 and 3 will move downward.

• Platforms 1 and 3 will move upward.

• Platform 2 will be even with Platform 1

• Platform 2 will be even with Platform 3

While teaching a lesson on the conservation of energy, a teacher diagrams the path of the motion of a swing moving back and forth.

Which energy transformation is the teacher MOST likely illustrating?

• thermal to kinetic

• potential to kinetic

• chemical to potential

• electrical to mechanical

Energy is transferred in an electrical circuit through

• static protons

• moving protons.

• static electrons.

• moving electrons.

Four identical cans are arranged on the shelves of the bookcase as shown.

Which can has the greatest potential energy?

• 1

• 2

• 3

• 3

Thomas watches an orange fall from a tree to the ground.

Which BEST describes the flow of energy as the orange falls and hits the ground?

• Solar energy → Potential energy → Heat energy

• Potential energy → Sound energy → Heat energy

• Kinetic energy → Potential energy → Sound energy

• Potential energy → Kinetic energy → Sound energy

An escalator is a compound machine that can be found in many buildings. The stairway on an escalator moves in a loop, which helps people move from one floor of a building to the next. The stairway loop moves with the help of a wheel and axle.

The stairway of the escalator is an example of which simple machine?

• lever

• screw

• wedge

• inclined plane

The primary function of a doorbell circuit is to convert electrical energy into

• sound

• motion.

• radiant energy.

• chemical energy.

While on a movie set, a stuntman jumps off the roof of a building. As he falls toward an airbag, what is increasing?

• gravity

• wind velocity

• kinetic energy

• potential energy