A hair dryer has an energy input of 1,500 J and gives out 1,200 J of useful energy. What is the efficiency of the hair dryer?
80% efficient
.8% efficient
1.25% efficient
300% efficient
80% efficient
In a house, why is it possible to have the lights turned on in one room, and the lights off in another room?
because in a house a series circuit is used to allow electrons to flow
because in a house a parallel circuit is used to allow electrons to flow
because in a house an open circuit is always used to allow electrons to flow
As long as there is some sort of circuit in the house, this is possible.
Because in a house a parallel circuit is used to allow electrons to flow
What is the purpose of a wire in a circuit?
to give off light energy
to turn on and off the light
to power the light
to allow electrons to flow through the circuit
to allow electrons to flow through the circuit
A student sets up a series circuit with 3 light bulbs connected to the same power source. If the student removes one of the three light bulbs, what will happen?
The two light bulbs will continue to shine because the circuit is still closed.
The two light bulbs will continue to shine because they are still connected to their power source.
The light bulbs will not shine because the circuit is now open.
The light bulbs will not shine because the power source has been removed.
The light bulbs will not shine because the circuit is now open.
A computer has an energy input of 10,000 J and gives out 7,000 J of useful energy. What is the efficiency of the computer?
70% Efficient
14.28% Efficient
0.7% Efficient
50% Efficient
70% efficient
The movement of negatively charged electrons in a complete circuit with a lamp and battery is shown to the right. Which statement best explains the movement of these electrons?
Positive charges are not attracted to negative charges
Positive charges are not attracted to positive charges
Negative charges are attracted to positive charges
Negative charges are attracted to negative charges
Negative charges are attracted to positive charges
A student is trying to create an electrical circuit but accidentally leaves the switch open and realizes the light bulb won’t turn on. Why does this occur?
Because there are no electrons if the switch is open
Because the electrons are not able to reach the positive side of the battery if the circuit is open
Because if the circuit is open, there is no battery
Because the open circuit causes the electrolyte to no longer function
Because there are no electrons if the switch is open
When you turn the light switch in your house off, which of the following most accurately explains what is happening?
The light switch has changed the power source.
The light switch has changed the directions that the electrons are moving.
The light switch has closed the circuit so the lights go off.
The light switch has opened the circuit so the lights go off.
The light switch has opened the circuit so the lights go off.
In the image to the right, what would the point W be?
Where potential energy is the lowest
Where kinetic energy is the highest
Where potential energy is the highest
Where kinetic energy and potential energy are equal
Where potential energy is the highest
What type of energy is used when you swim?
Light energy
Potential energy
Heat energy
Mechanical energy
Mechanical energy

Closed circuit
What type of energy is displayed when thunder rumbles?
Light energy
Sound energy
Electrical energy
None of the above
Sound energy
A boulder begins rolling down a hill. Which of the following answer choices is the most accurate?
Potential energy is decreasing and kinetic energy is increasing.
Potential energy is increasing and kinetic energy is increasing.
Potential energy is decreasing and kinetic energy is decreasing.
Potential energy is increasing and kinetic energy is decreasing.
Potential energy is decreasing and kinetic energy is increasing.
What type of energy powers a blender?
Light energy
Sound energy
Electrical energy
Chemical energy
Electrical energy
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Open system
What type of energy are batteries used for?
Electrical energy
Light energy
Chemical energy
All of the above
Electrical energy