Energy Unit Review

When a hair dryer is being used, one of the energy transformations that takes place is ____.

• chemical to electrical

• electrical to chemical

• electrical to mechanical

• mechanical to electrical

In the simple act of lighting a match, chemical energy stored in the match head is transformed into heat and light. What is true about this energy transformation?

• Most of the energy is lost when the match is struck.

• New energy in the form of light and heat is created when the match is struck.

• All of the potential chemical energy is transformed into heat and light energy.*

• Some of the chemical energy is transformed into heat and light and the rest is converted into matter.

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NGSS.MS-PS3-5

On a cold, winter day, Sheena rubs her hands together. Stored chemical energy is transformed into mechanical energy. Due to the Law of Conservation of Energy some of the energy is also transformed into ____.

• heat energy

• light energy

• solar energy

• kinetic energy

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NGSS.MS-PS3-5

The stored energy in a battery can BEST be described as:

• kinetic

• nuclear

• thermal

• chemical

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NGSS.HS-PS1-2

All of the following are forms of energy EXCEPT:

• heat

• light

• friction

• electrical

A lamp that plugs into a wall socket draws energy, which flows through a thin wire in the bulb, causing it to heat up until it glows. What energy transformations are taking place?

• Chemical → light → electrical

• Mechanical → sound → light

• Thermal → solar → electrical

• Electrical → thermal → light

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NGSS.MS-PS1-4

An electric pencil sharpener uses electricity to make its motor spin. The pencil sharpener also makes noise and heats up. Which observation of the pencil sharpener demonstrates the law of conservation of energy?

• The amount of electrical energy used equals the total amount of mechanical, sound, and thermal energy produced.

• The amount of energy used by the electric pencil sharpener is greater than an electric lamp.

• The electric pencil sharpener only uses energy when it is being used to sharpen a pencil.

• The electric pencil sharpener is easier to use than the older version that was cranked by hand.

Tags

NGSS.MS-PS3-5

When energy enters a system and then comes out of the system later, the law of conservation of energy states that–

• some of the energy that entered the system will remain in the system.

• the energy will always create a change in the properties of the parts of the system.

• the form of energy that comes out of the system must be the same form that entered.

• the amount of energy coming out of the system must equal the energy that entered the system.

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NGSS.MS-PS3-4

NGSS.MS-PS3-5

In which of the following scenarios would this energy transformation be observed?

chemical → light → heat

• Plucking a guitar string

• Lighting a match

• Turning on a fan

• Starting a car

The law of conservation of energy states ___.

• electrical energy can be transformed into other forms

• energy can be created and destroyed

• energy is never created nor destroyed

• what goes up must come down

Tags

NGSS.MS-PS3-5