Forms and Uses of Energy
Which of the following best explains how someone can recognize a situation in which energy is acting on an object?
A The object has a certain shape.
B The object has a lot of mass.
C The object remains perfectly still.
D The object changes in some way.
D The object changes in some way.
For an electrically charged object to repel another object, what must happen?
A The objects must touch.
B The objects must have opposite charges.
C The objects must have similar charges.
D The objects must be very light.
C The objects must have similar charges.
Gherant and Julio were investigating electricity in science class by making a circuit. The circuit contains a wire, a battery, and a bulb. They notice when they were finished lighting the bulb, the bulb felt warm. Why does the bulb feel warm after it has been lit?
A. The light bulb was faulty and did not work correctly.
B. Some of the electrical energy was changed to heat.
C. The light bulb was not connected to a closed circuit.
D. Some of the electrical energy was destroyed.
B. Some of the electrical energy was changed to heat.
Ben puts a flashlight together. He used new batteries and a new bulb. He pushed the switch, but the flashlight did not go on. What is most likely the reason?
a. There is no closed circuit.
b. The switch is not working.
c. Two batteries are not enough.
d. The battery is not connected to the bulb.
a. There is no closed circuit.
A force acts on objects and causes them to move. Which of the following is NOT an example of force causing motion?
A. A spinning propeller on a plane
B. Turning the pedals of a bike
C. Hammering a nail into wood
D. A lamp sitting on a desk
D. A lamp sitting on a desk
5. Brian’s dad has asked him to mow the yard. First, he adds gasoline to the mower. To start the mower’s gasoline engine, he must pull the cord. What form of energy is used as Brian pulls the cord?
A. Electrical energy
B. Chemical energy
C. Sound energy
D. Mechanical energy
D. Mechanical energy
On a winter day, Samantha was at the park and decided to go down a plastic slide. After sliding down the slide, Samantha touches her friend Kim. They both feel a sudden shock. What created the shock?
A. Heat was transferred from Samantha’s body to Kim’s body.
B. A chemical change occurred that created electricity between their bodies.
C. A static charge was created as Samantha went down the slide.
D. Whenever someone touches another person, electricity is released.
C. A static charge was created as Samantha went down the slide.
A toaster is plugged into the wall and turns a piece of bread into toast.
Which of the following best explains how it works?
A It turns mechanical energy into light energy.
B It gets chemical energy from gases in the air.
C It transforms electrical energy to the energy of motion.
D It transforms electrical energy into heat energy
D It transforms electrical energy into heat energy
The flow of electricity requires a closed loop, or circuit. Which answer shows a circuit that would allow a light bulb to light?
A. Battery > Light bulb
B. Light bulb > Copper wire > Switch
C. Battery > Copper wire > Switch
D. Battery > Copper wire > Light bulb
D. Battery > Copper wire > Light bulb
The gravitational force between two objects can cause the objects to move. If Jon has two rubber balls and dropped them, which of the following would affect the gravitational force?
A. Magnetism
B. Shape
C. Temperature
D. Mass
D. Mass
Which statement best defines energy?
a. Energy is a force.
b. Energy causes all change.
c. Movement causes energy changes.
d. Energy is light and heat.
b. Energy causes all change.
7. Ricardo rubbed a balloon on his shirt and then held the balloon over some very small bits of paper. Ricardo observed that the paper was attracted to the balloon. What caused the paper to be attracted to the balloon?
a. The balloon became negatively charged when Ricardo rubbed it on his shirt and this caused the positively charged pieces of paper to be attracted to the balloon.
b. The balloon became negatively charged when Ricardo rubbed it on his shirt and this caused the negatively charged pieces of paper to be attracted to the balloon.
c. The balloon became positively charged when Ricardo rubbed it on his shirt and this caused the positively charged pieces of paper to be attracted to the balloon.
d. The balloon became static electricity and paper is attracted to static electricity.
a. The balloon became negatively charged when Ricardo rubbed it on his shirt and this caused the positively charged pieces of paper to be attracted to the balloon.
Using a wind mill to create electricity is an example of:
a. transforming solar energy into mechanical energy.
b. transforming mechanical energy into electrical energy.
c. transforming electrical energy into wind energy.
d. transforming electrical energy into mechanical energy.
b. transforming mechanical energy into electrical energy.
Which of following is the best conductor of electricity?
A. a glass rod
B. a rubber rod
C. a copper rod
D. a wooden rod
C. a copper rod
Milton is conducting an experiment to see how far a marble will roll when he releases it at the top of an inclined plane. Why does the marble speed up as it travels down the inclined plane?
A. The marble has a greater mass as it travels faster.
B. The force of gravity pulls the marble down the inclined plane.
C. The force of friction is reduced because the marbles surface is smooth.
D. The marble has less magnetic attraction to the inclined plane as it travels.
B. The force of gravity pulls the marble down the inclined plane.
Using a wind mill to create electricity is an example of
a. transforming solar energy into mechanical energy.
b. transforming mechanical energy into electrical energy.
c. transforming electrical energy into wind energy.
d. transforming electrical energy into mechanical energy.
b. transforming mechanical energy into electrical energy.
Sonia noticed students from a science class conducting an investigation. They were rubbing a balloon on their shirt and then placing the balloon close to an empty soda can. As the balloon approached the can, the can began to move. What caused the can to move?
A. The balloon became negatively charged when the students rubbed it on their shirt and this caused the can to be attracted to it and move.
B. The balloon became negatively charged when the students rubbed it on their shirt and this caused the negatively charged can to be attracted to it and move.
C. The balloon became positively charged when the students rubbed it on their shirt and this caused the positively charged can to be attracted to it and move.
D. The balloon became static electricity when the students rubbed it on their shirt and the can was attracted to static electricity and moved.
A. The balloon became negatively charged when the students rubbed it on their shirt and this caused the can to be attracted to it and move.
Kimberly gets tired of waiting for her brothers to finish playing golf. She presses on the pedal of the golf cart and it starts to move. Which of the following explains how the golf cart is able to move?
A. Mechanical energy from Kimberly's foot is transformed to electricity that moves the cart.
B. Light energy absorbed from the Sun is transformed to electrical energy that moves the cart.
C. Sound energy created by the cart is transformed to heat energy that moves the cart forward.
D. Electrical energy stored in the battery is transformed to mechanical energy that moves the cart.
D. Electrical energy stored in the battery is transformed to mechanical energy that moves the cart.
What is the difference between conductors and insulators?
A. A conductor allows electricity to flow easily, while an insulator does not.
B. An insulator allows electricity to flow easily, while a conductor does not.
C. A conductor has a static electrical charge, while an insulator does not
D. An insulator is usually a metal, while a conductor is not a metal.
A. A conductor allows electricity to flow easily, while an insulator does not.
Brian and Emily are testing different paper airplane designs to see which will allow a plane to go the farthest. Emily folds her plane and attaches a paperclip to the front of it. After she throws the plane, it travels about fifty feet and then starts to fall to the ground. Why does the plane eventually fall to the ground?
A. The force of air resistance stops acting on the plane
B. The plane was not designed to carry a load like the paperclip
C. The force of gravity is greater than the forces keeping the plane in the air.
D. The paperclip creates a magnetic force that attracts the plane to the ground
C. The force of gravity is greater than the forces keeping the plane in the air.
Amber visits a theme park that has no roller coaster that travels upside down. Which of the following is the best explanation for why the roller coaster car stays in contact with the track when it travels upside down?
A. The track and car are held together by a series of strong magnets.
B. The car has large amounts of thermal energy that binds it to the track.
C. The car has chemical energy that resists the effect of gravity when it is upside down.
D. The car has mechanical energy and is fast enough that gravity cannot pull the car down.
D. The car has mechanical energy and is fast enough that gravity cannot pull the car down.
The table provided describes four different scenarios involving charged and uncharged objects. In how many of the scenarios will the two objects be attracted?
Scenarios
A negatively charged object is brought near an uncharged object.
A positively charged object is brought near a positively charged object.
A negatively charged object is brought near an uncharged object.
A negatively charged object is brought near a positively charged object.
A 1
B 2
C 3
D 4
C 3
Jennifer is getting ready for school on a cold day in February. She wants to make sure her is completely dry before she leaves her house. She plugs her hair dryer into the wall outlet and turns it on. Which of the following describes one of the steps involved in using energy to dry Jennifer's hair?
A. Thermal energy is changed into mechanical energy, which makes the motor in the hair dryer move.
B. Electrical energy is changed into heat energy, which makes the motor in the hair dryer move.
C. Mechanical energy is changed into heat energy, which makes the motor in the hair dryer move.
D. Electrical energy is changed into mechanical energy, which makes the motor in the hair dryer move.
D. Electrical energy is changed into mechanical energy, which makes the motor in the hair dryer move.
Tami goes into the kitchen and flips the switch to turn on the lights. What role does the switch play in the light coming on?
A. Opens a circuit, stopping electricity from flowing.
B. Closes a circuit, allowing electricity to flow.
C. Opens a circuit, allowing electricity to flow.
D. Closes a circuit, stopping electricity from flowing.
B. Closes a circuit, allowing electricity to flow.
Because the force of gravity is so strong, it appears to attract all objects equally, regardless of mass. Which of the following is illustrated by this idea?
A. Earth orbits the Sun in the same amount of time it takes the Moon to orbit Earth.
B. A rubber ball will bounce much higher than a wooden ball, even if they weigh the same.
C. Magnets can both repel and attract each other, depending on how they come into contact.
D. A bowling ball and a peanut will fall to the ground at the same rate when someone drops them.
D. A bowling ball and a peanut will fall to the ground at the same rate when someone drops them.