Science Section II Test p. 3 of 3

What does Ohm’s law state?

• I = R/V

• V = I/R

• I = V/R

• R = I/V

• V = I + R

What does the resistance (R) in Ohm’s law represent?

• a quantity that resists the flow of current, like friction

• the current flowing through the battery

• the voltage in a circuit

• the total charge in a battery

• the power of the battery

In the example with the fork and a wall outlet, why can a dangerous electric shock happen even though the voltage is only 120 V?

• because 120 V is a very high voltage

• because the fork is an insulator

• because the fork is a good conductor, allowing many charges to flow

• because the outlet has a very high resistance

• because the fork blocks the current from flowing

What does voltage create in an electric circuit?

• the flow of electrons

• the amount of resistance

• the temperature of the wire

• the power of the circuit

• the potential difference that allows current to flow

Why does the tungsten filament in an incandescent lightbulb glow?

• because it is cooled by the air

• because it reflects light from outside

• because it contains water that heats up

• because current flowing through it heats it up until it glows

• all of the above

What is the purpose of the glass bulb in a lightbulb?

• to glow and produce light

• to conduct electricity

• to protect people from touching the hot tungsten filament

• to cool down the filament

• to speed up the electrons

How much energy is equivalent to one kilowatt-hour?

• 1,000 joules

• 3,600 joules

• 36,000 joules

• 3,600,000 joules

• 360 joules

What causes the electrons in your home's wires to start moving when you flip a light switch?

• electrons traveling from the power plant at millions of meters per second

• electrons moving quickly down the wire like dominoes

• an electric field that accelerates the electrons already in the wire

• the physical movement of electrons pushed by the power plant

• electrons colliding with each other to transfer energy

Tags

NGSS.MS-PS2-5

What happens to the resistance of a wire as its temperature increases?

• It stays the same.

• It increases.

• It decreases.

• It becomes zero.

• It becomes negative.

Tags

NGSS.MS-PS1-4

What is a superconductor?

• a material that heats up quickly when current flows

• a material that has very high resistance at room temperature

• a material that allows electricity to flow only at high temperatures

• a material that has zero resistance at very low temperatures

• a material used only in household wiring

Tags

NGSS.HS-PS3-5