Electricity and Magnetism Quiz

Two objects move away from each other. What happens to the gravitational attraction between them?

• It decreases.

• It increases.

• It becomes zero.

• It does not change.

Which of the following statements about gravitational fields is true?

• Gravitational fields affect objects only when two objects are touching.

• Gravitational fields affect objects only if the objects are not in contact.

• Any object that has mass is surrounded by a gravitational field.

• Only very massive objects, such as Earth, are surrounded by a gravitational field.

When a rocket attempts to launch, its engine exerts a force downward. The rocket will not launch until the force of the engine is greater than the weight of the rocket. Why?

• The forces must be equal and balanced for the rocket to move.

• The force of the engine must be twice as strong as the force of gravity for the rocket to move.

• The rocket must move at a constant velocity to take off.

• The force of the engine must be greater than the force of gravity to produce a net force upward.

A gas giant (Jupiter, Neptune, Saturn, and Uranus) is a type of planet. Four gas giants orbit the sun. The table gives the average distance of each of these planets from the sun. At which of the gas giants is the sun's gravitational field the strongest.

• Jupiter

• Neptune

• Saturn

• Uranus

A student rubs a balloon with a wool cloth several times, giving the balloon a negative charge. Which process is the student using to charge the balloon?

• charging by friction

• charging by induction

• charging by conduction

• charging by insulation

Student 1 claims that electric field can affect objects only when the objects are in direct contact. Student 2 does not agree with student 1. Which statement should Student 2 use as evidence that Student 1 in INCORRECT?

• An atom's neutrons and electrons are located in its nucleus.

• A balloon will stick to a wall only if the balloon has an overall charge.

• Rubbing a plastic rod with silk cloth transfers protons from the cloth to the rod.

• Two negatively charged balloons will repel each other when brought close together without touching.

An object can become electrically charged if it gains or loses which particles?

• volts

• neutrons

• protons

• electrons

Which of the following best describes a magnetic field?

• a measure of the length of the magnet

• an invisible region that surrounds the north pole of a magnet

• an invisible region that surrounds the north pole of a magnet

• a region around a magnet in which you can measure magnetic forces

Two negatively charged particles are 1 millimeter apart. The electric force between then is 20 newtons. How will the amount of electric force between the particles change if the particles move closer together?

• The electric force will increase.

• The electric force will decrease.

• The electric force will stay the same.

• The electric force will disappear.

Which of the following is evidence that a magnetic field surrounds a magnet?

• When a paper clip is placed on a bar magnet, it sticks to the magnet.

• When the north poles of two magnets are brought near each other, they push apart without touching.

• When a magnet is placed on a metal surface it sticks to the surface.

• When you touch a metal doorknob sometimes you receive a shock.