Physical Science Electromagnetism QUIZ Study Guide

1)A 10.0 kilogram mass of iron on earth exerts a downward force of 98 Newtons. On the moon this same 10.0 kilograms of iron is weighed and found to exert a downward force of 16.3 Newtons. How is this possible?

A) / The earth is farther away reducing the pull.
B) / Weight is the same everywhere, but mass changes.
C) / Mass begins to evaporate in the vacuum of space.
D) / The gravity on the moon is one sixth the gravity of Earth.

2)Renaldo and Nasreen build an electromagnet by wrapping a wire around a nail and connecting the wire to both terminals of a battery. When they test the electromagnet, it can pick up 6 paper clips. Their teacher wants all groups to pick up at least 10 paper clips. What could Renaldo and Nasreen do to increase the number of paper clips their electromagnet picks up?

A) / make the wire longer
B) / remove the nail from the center of the wire
C) / increase the number of loops of wire around the nail
D) / spread the loops of wire apart on the nail so they do not touch

3)Considering the factors that affect gravitational pull, in which location would the gravitational pull from the earth be SMALLEST on you?

A) / visiting friends at the beach
B) / visiting Santa on the second floor of the mall
C) / visiting Uncle Chrissy in the Himalayan Mountains
D) / visiting cousin Snelfu in his submarine at the bottom of the ocean

4)When we touch a Van de Graaff generator, our hair may stand up if it is dry. This happens only if the strands of our hair

A) / acquire atoms.
B) / repel each other.
C) / attract each other.
D) / gain negative charge.

5)Which is an example of gaining a static charge by conduction?

A) / Rubbing a balloon against your hair.
B) / Shuffling your shoes across a carpet.
C) / Bringing a charged rod near an electroscope.
D) / Touching your car on a cold day and getting a shock.

6)After turning off the television, you approach it. As you get close, but not touching it, the hairs on your arm start to stand up. This is an excellent example of static charge built up by

A) / conduction.
B) / convection.
C) / friction.
D) / induction.

7)Mike wants to negatively charge a small rubber ball. Which of these methods would successfully charge the ball?

A) / heating the ball in boiling water
B) / running the ball over a strong magnet
C) / rubbing the ball back and forth on carpet
D) / dropping the ball from a tall bulding

8)Sal and Marie were experimenting with bar magnets in science class, picking up chains of paper clips. Where should they expect the magnetic force of the bar magnet to be the strongest and pick up the most paper clips?

A) / at both Poles
B) / at the South Pole
C) / at the North Pole
D) / in the center of the bar magnet

9)An astronaut travels to the moon. What is true regarding her mass and weight?

A) / Her mass and weight are greater on Earth.
B) / Her mass and weight are the same on the moon as on Earth.
C) / Her mass is the same on the moon and Earth, but her weight is greater on Earth.
D) / Her weight is the same on the moon and Earth, but her mass is greater on Earth.

10)The circumstance MOST LIKELY to cause a compass to give an erroneous reading is standing too close to

A) / the ocean.
B) / a mountain.
C) / an electric power line.
D) / a heavily populated area.

11)The Sun has more gravity than the other planets in our solar system because the Sun is

A) / hotter.
B) / more massive.
C) / made of plasma.
D) / undergoing fusion.

12)

During induction, a positively charged rod is brought near to but not touching the electroscope. The presence of the charged object above the plate of the electroscope induces charges to move down into the gold leaves, giving the electroscope an overall positive charge. The positive leaves repel. The same process occurs when a negative rod is brought close to the electroscope. This time, the negative charges flow through the electroscope to the leaves. The leaves, once again, repel. Whether the charge is positive or negative, in each case, the experiment shows that

A) / like charges repel.
B) / opposite charges repel.
C) / friction produces current.
D) / electrons produce a current.

13)If you hold a balloon by a string and the balloon moves toward your sweater and sticks there, what would you infer?

A) / That the balloon and the sweater have no charges.
B) / That the balloon and the sweater have like charges.
C) / That the balloon and the sweater have neutral charges.
D) / That the balloon and the sweater have opposite charges.

14)

Students hypothesized that by running an electric current through the wire of the apparatus shown here, they could cause a non-magnetic nail to exhibit magnetic properties. What would be a reasonable way to test this?

A) / Weigh the nail first while before turning the current on and again while the current was on.
B) / Put the nail in water before turning the current on and again after turning the current off.
C) / Examine the nail under a microscope before turning the current on and again after turning the current off.
D) / See if iron filings will stick to the nail before turning the current on and again while the current was on.

15)Jacob floated a long steel sewing needle on a small piece of cork in a glass of water. He noticed that as he turned the glass around, the cork and needle continued to point toward his backyard. Even after he turned the small floating cork around gently, the needle finally pointed toward the backyard. What is the MOST LIKELY conclusion Jacob will draw?

A) / There is a large magnet in the backyard.
B) / Jacob’s backyard is on the north side of his house.
C) / The backyard is downhill from where Jacob is standing.
D) / A gentle breeze is causing the needle to point toward the backyard.

16)

During physical science, Ms. Greene challenged her students to produce an energy transformation. James and Jill wrapped a 4-inch nail with a coil of fifty turns of wire. They connected one end of the coil to one terminal of a knife switch. They connected the other terminal of the knife switch to the battery. Finally, they connected the end of the coil to the other terminal of the battery.
James held the tip of a 1-inch nail near the flat end of the 4-inch nail. Jill closed the knife switch quickly and then opened it. The 1-inch nail was pulled toward the 4-inch nail.

James and Jill used a battery as a source of electricity to construct
a(n) ______that created ______energy that caused the nail to move.

A) / motor; electrical
B) / generator; magnetic
C) / generator; electrical
D) / electromagnet; magnetic

17)Wires used in the cables of household gadgets have a plastic covering. This is because plastics

A) / absorb heat well.
B) / can be bent to any shape.
C) / are poor conductors of electricity.
D) / are cheaper than other cover materials.

18)Jermaine and Lashonda each rub their dry hair with inflated balloons. While doing this, the other students notice that their hair is starting to stick straight out.
Next, the teacher takes the balloons and places them right next to one another. However, the balloons will not stay next to each other, as they normally would. Instead, they spring apart in opposite directions.
What is causing these balloons to push each other away?

A) / There must be a vent in the classroom blowing the two balloons apart.
B) / They have each gained negative charge from the hair rubbing, and like charges repel each other.
C) / They have each gained negative charge from the hair rubbing, and like charges attract each other.
D) / The rubber balloons are simply bouncing off each other the way a rubber ball bounces off the floor.

19)Magnets and electromagnets can both be used to pick up metal items like iron nails.
Although they are alike, there is a difference between magnets and electromagnets. An example of this is that increasing the current running through the electromagnet's wire will make it stronger.
What is another difference?

A) / Increasing the amount of wire loops will increase the strength of an electromagnet.
B) / Increasing the amount of wire loops will increase the strength of a magnet.
C) / There is no other difference between electromagnets and magnets.
D) / Electromagnets are always stronger than regular magnets.

20)Mrs. Adams class decides to try an experiment. She rubs a blown up balloon on Sandy's head. After this, she takes the balloon and places it on the side of the wall, where it sticks, instead of falling to the ground. Also, Sandy's hair is now sticking almost straight out.
What causes Sandy's hair to act this way?

A) / magic
B) / wind currents
C) / static electricity
D) / current electricity

21)Renaldo and Nasreen build an electromagnet by wrapping a wire around a nail and connecting the wire to both terminals of a battery. When they test the electromagnet, it can pick up 6 paper clips. Their teacher wants all groups to pick up at least 10 paper clips. What could Renaldo and Nasreen do to increase the number of paper clips their electromagnet picks up?

A) / make the wire longer
B) / remove the nail from the center of the wire
C) / increase the number of loops of wire around the nail
D) / spread the loops of wire apart on the nail so they do not touch

22)Reva placed an iron nail close to a magnet. What happened?

A) / The nail bent.
B) / The nail moved to the magnet.
C) / The nail stayed in the same place.
D) / The nail pushed away from the magnet.

23)If a positively charged particle moves into a magnetic field traveling in a straight line, how would you expect its motion to change?

A) / The particle would slow and stop moving.
B) / The particle would travel in a curved path.
C) / The particle would continue traveling in a straight line.
D) / The particle would make a right angle turn and then continue traveling in a straight line.

24)An electrician wraps rubber electrical tape around a copper wire. Since rubber is an insulator, which statement best explains the point of wrapping rubber around a copper wire?

A) / Rubber stops charges from flowing. This protects people by stopping electricity from flowing.
B) / Charges flow better through rubber. This makes electricity flow better through the wire.
C) / The rubber tape keeps the wire from falling apart.
D) / The rubber keeps the copper wire from melting.

25)An electromagnet is created using a battery, an insulated copper wire and an iron nail. The wire is wrapped around the nail 20 times and attached to the battery. Which pair of changes will definitely increase the strength of the electromagnet?

A) / Increase the voltage of the battery and decrease the number of turns of the coil.
B) / Decrease the voltage of the battery and decrease the number of turns of the coil.
C) / Increase the voltage of the battery and increase the number of turns of the coil.
D) / Decrease the voltage of the battery and increase the number of turns of the coil.

26)A scientist is giving a demonstration with a Van de Graaff generator in a class about electrostatics. The scientist can detect the type of charge on the Van de Graaff generator by

A) / bringing a positively charged balloon near it.
B) / seeing if it picks up bits of paper from a surface.
C) / touching it with a metallic rod that conducts charge.
D) / testing if it attracts a neutral sphere made of plastic.

27)You rub a balloon on your head and it becomes negatively charged. The balloon will be MOST attracted to

A) / a piece of metal.
B) / positively charged hair.
C) / the neutrally charged wall.
D) / another negatively charged balloon.

28)

The attracting and repelling forces of magnets are used in countless objects, from refrigerator doors to maglev trains. Refrigerator doors use the attraction of magnets to stay closed, while maglev trains use magnetic repulsion to hover above rails. The center magnet in the picture is hovering between two magnets, making it appear to float. Which best explains how the center magnet is able to hover between two other magnets?

A) / The magnets are stacked so that similar poles are facing one another.
B) / The opposite poles of each magnet are facing each other, so they repel.
C) / The middle magnet is repelling the top magnet while attracting the bottom.
D) / The middle magnet is attracted to the top magnet, but held down by gravity.

29)A simple motor converts ______energy into ______energy.

A) / magnetic; electrical
B) / electrical; magnetic
C) / electrical; mechanical
D) / mechanical; electrical

30)Donna is trying to make an electromagnet to pick up old nails around her driveway. Which of these materials would be best to use for the core in order to make the strongest electromagnet to pick up the most nails?

A) / iron nail
B) / wooden stake
C) / plastic ruler
D) / cardboard tube