Non contact Forces

Which of the following forces can push (repel) and pull (attract)?

• Magnetic Force

• Electric Force

• Gravitational Force

• Both Magnetic and Electric Force.

• All Three, Magnetic, Electric and Gravitational Force.

When two magnets repel, they ________________

• change color
• pull together
• push apart
• get colder

Iron filings and bar magnets are placed on a piece of paper. Explain the pattern on the diagram below. Where is the magnetic field the strongest?

• The magnetic field is only strong at the north pole

• The magnetic field is only strong at the south pole

• The magnetic field is strongest at the magnet’s poles.

When placed at equal distances apart, the greatest gravitational attraction will be between two

• skateboards

• bowling balls

• school buses

As the product of two objects' masses increases, the pull of gravity

• Increases
• Decreases
• Stays the same

What types of charges attract?

• Positive and Positive
• Positive and Neutral
• Negative and Neutral
• Positive and Negative

Electric charges that are alike _______ each other.

• Attract
• Repel

Moving a magnet near a compass can cause the compass needle to move, even though the magnet does not touch the compass. This observation is evidence for which characteristics of magnetic fields?

• There is a north and south pole on a magnet.

• They can exert a force accross a distance.

• Magnetic fields do not exist.

You made an electromagnet to pick up pins. It did not pick them up until the nail was next to the pins. This is because

• The smaller the distance between two electromagnets the greater the force.

• As distance increases between two electromagnets the force becomes greater.

Magnetic Force is

• A force of attraction between any two objects in the universe

• A force that acts between objects that are electrically charged

• The force of attraction or repulsion between unlike or like poles

• A contact force that resist motion between two objects that are touching