Physics and Magnetism Quiz

A bar magnet attracts a paper clip, then a second paper clip is attracted to the bottom of the first paper clip until four paper hang from the vertical bar magnet as shown. .

.What causes a paper clip to hang from a bar magnet?

• The paper clip is made of plastic.

• The paper clip is repelled by the magnet.

• Its atoms' magnetic fields align because of the magnetic field of the bar magnet.

• The paper clip is heavier than the magnet.

What is required to move a positively charged particle from Point H to Point G in an electric field?

• No work is required.

• Work is required because the particle is moving against the electrical field., work is required to move it from Point H to Point G.

• The particle moves automatically.

• The particle is repelled by the field.

Which materials would best help to study a magnetic field formed by the movement of electricity?

• Plastic, rubber, glass

• Battery, wire, compass

• Wood, paper, cloth

• Stone, sand, metal

Two positive point charges are placed near each other. Charge A has a 12.5 mC charge and B has an 18.2 mC charge. Which of these is true about the electric field lines between these two charges?

• The lines cross each other frequently.

• The lines are denser around Charge A.

• The electric field lines never cross and are denser around point Charge B.

• The lines are equally dense around both charges.

Iron filings are evenly spread across a surface, which is then covered by a plastic sheet. Two bar magnets are placed on top of the plastic. The iron filings move in response to the magnets, Where is the magnetic field strongest when iron filings are spread across a surface with bar magnets on top?

• Near the center of the magnets

• Near the pole of the magnets

• Equally strong everywhere

• At the edges of the magnets

What causes the bend of a stream of water when a rod with a net positive charge is held near it?A rod has a net positive charge. The rod is held a stream of water causing the stream of Water to bend toward the rod. What causes the bend of the stream of water?  

• Water molecules are non-polar.

• Water molecules are polar, so the negatively charged side of the molecules is attracted to the rod.

• The rod repels the water molecules.

• The water molecules are neutral.

Object B is 10 cm from Object A and has a charge of +Q. Object C is 20 cm from Object A and has a charge of +2Q. Which statement is true about the relatives’ strengths of the electric force from Objects C on Object A. What is true about the relative strengths of the electric force from Objects C on Object A?

• The force from object B is weaker than the force from object C.

• The force from object B is twice as great as the force from object C.

• The force from object C is twice as great as the force from object B.

• The forces are equal.

What is true about the electric field lines of point charges?

• Electric field lines enter positive charges and leave negative charges.

• Electric field lines leave positive charges and enter negative charges.

• Electric field lines are circular.

• Electric field lines are parallel.

Two small cubes have 8 Mc charge each. First the cubes are placed 10 cm apart, and then they are moved closer, so they are 2 cm apart. Which of these correctly describes how the force between the charge’s changes? How does the force between two charges change when they are moved closer together?

• The force becomes weaker and less repulsive.

• The force remains the same.

• The force between the charges becomes stronger and more repulsive.

• The force becomes attractive.

What does the model show about three particles interacting electrically?

• M>L>K

• M<K<L

• M=L

• M>K>L