Forms of Energy

Which of the following items transfers electrical energy into sound energy?

• lamp

• doorbell

• calculator

• candle

Carly put her pencil in a cup of water. Now her pencil looks like it is broken. Which best explains why Carly's pencil looks broken?

• Light is reflected.

• Light is refracted.

• Light is absorbed.

• Light is bright.

A switch is part of a circuit. Which best describes the function of a switch?

• A switch stops and starts the flow of electricity.

• A switch keeps the wires from getting too hot.

• A switch makes a battery stronger.

• A switch opens to complete a circuit.

The picture below shows a tree near a lake. Ilan sees a mirror image of the tree in the water of the lake. What causes this mirror image?

• black light

• refracted light

• reflected light

• absorbed light

Which of the following items transfers electrical energy into light and heat energy?

• power plant

• connecting wires

• fan

• light bulb

Which best explains why light travels in a straight line?

• Light waves don't travel in a straight line.

• Light waves travel in a straight line because sound waves travel in a straight line.

• Light waves will always travel in a straight line, even if they strike an object or travel from one medium to another.

• Light waves will travel in a straight line if they do not interact with an object.

Why is sound a form of energy?

• Sound waves carry energy that can cause motion or create change.

• Sound and energy are not related.

• Energy is present only in loud sounds.

• Energy is present only in high-pitched sounds but not in low-pitched sounds.

Energy is changed from one form to another during an energy transfer. Which of the following examples describe the transfer of electrical energy into another form of energy?

• a motor making noise

• a heater that feels warm

• a light bulb lighting up

• all of these examples describe a transfer of energy

Heat and magnetism are two forms of ___________ because they can cause change or create motion.

• matter

• energy

• solids

• animals

When light strikes an object or travels from one medium to another, it can be reflected, refracted, or ___________.

• melted

• evaporated

• absorbed

• grouped