Electricity and Heat Review

A fan is plugged into an extension cord. The extension cord is plugged into a wall outlet. How does the extension cord help the fan work?

• The extension cord makes the fan more powerful.

• The extension cord makes the fan easier to operate.

• The extension cord transfers sound energy to the fan.

• The extension cord transfers electric currents from the outlet to the fan.

An electric fence used to contain cattle works by transmitting energy through a conductor creating an electric ___________.

• current

• ripple

• wave

A flow of electrical charges is known as _________.

• resistance

• electrical current

• static electricity

• voltage

In an electric circuit, a battery can act as a __________.

• voltage source

• conductor

• insulator

• resistor

A conductor is a ___________.

• a material that increases the number of charged particles

• material that increases the amount of electricity

• material through which electricity flows easily

• material that stops the flow of energy

You are asked to design a product that will change electrical energy to heat energy. Choose the item you would research while developing your product.

• Hair dryer

• Alarm clock

• Ceiling fan

• Cell phone

Amy touched a machine called a Van de Graaf generator. When she touched the generator all of her hair on the top of her head stood up. When she removed her hand from the generator, her hair fell back to its normal state. What conclusion can you draw from Amy touching the generator?

• Charged particles are being pulled from the air.

• Charged particles are being pulled from the floor.

• Charged particles are being destroyed.

• Charged particles are being moved from one object to another.

A switch in a circuit__________.

• acts as an insulator

• absorbs electricity

• allows or stops the flow of electricity

• keeps the flow of electricity at a safe level

An object in an electrical circuit that resists the flow of energy is called

• a magnet

• a compass

• a voltage

• a resistor

A farmer needed to keep his baby chicks warm. He placed a light in their cage. Which sentence best explains the farmer's thinking of placing a light in the cage?

• The farmer thought the light would transfer thermal energy to the chicks' cage.

• The farmer thought that the chicks would be healthier if they were not in the dark.

• The farmer thought that the chicks would eat more to stay warm if they can see their food.

• The farmer thought that the light would encourage the chicks to huddle together to keep themselves warm.