Magnetic Forces

Magnetic Forces

Multiple Choice

Quick Check:

An object placed 3 meters up on a wall and has 15 N weight. What is the gravitational potential energy of the object?

GPE = weight x height

• 45 J

• 5 J

• 18 J

• 12 J

Multiple Choice

Quick Check:

An object moving at a constant speed of 4 m/s. If the mass of the object is 10 kg. What is the kinetic energy of the object?

KE = 0.5 x mass x velocity^2

• 80 J

• 40 J

• 14 J

• 90 J

Poll

The top picture shows a bar magnet with the poles labeled N and S. The magnet was cut into two pieces-one pieces and one long piece. How should the cut end of the short piece of magnet be labeled?

• N

• S

• No label; it no longer has N or S pole on the cut end.

How is the plant floating in the air?

Watch the video!

Open Ended

How is the plant floating in the air?

Multiple Select

What are objects you know a magnet does NOT attract?

• Wood

• Plastic

• Rubber

• Iron

• Metal

Magnet

A piece of metal that attracts objects with iron in them

Open Ended

Why is a magnetic force called a non-contact force?

Magnetic Poles

The colors and labels on some magnets identify a magnet's magnetic poles.

Magnetic Pole

Is a place where the force a magnet applies is strongest. There are two magnetic poles on all magnets, (North Pole & South Pole). If you break a magnet, each piece will have a north and a south pole.

Multiple Choice

What will happen when like poles of two magnets are brought near each other?

• Repel or push away from each other

• Attract

Multiple Choice

What will happen when opposite poles of two magnets are brought near each other?

• Repel or push away from each other

• Attract

What is happening to the iron filing in the image?

Magnetic Field

An invisible magnetic field surrounds a magnet. The magnetic field applies forces to other magnets or other magnetic material even when they are not in the contract.

Multiple Choice

Which of the following statements explains why magnet A appears to be floating above magnet B?

• Like poles repel each other

• Opposite poles attract each other

• Opposite poles repel each other

• Like poles attract each other

Multiple Choice

Mohammed can make his toy car move using a magnet inside the box.

What name is given to a force that acts on an object without touching it?

• A non-contact force

• A friction force

• A contact force

Multiple Choice

The top picture shows a bar magnet with the poles labeled N and S. The magnet was cut into two pieces-one pieces and one long piece. How should the cut end of the short piece of magnet be labeled?

• N

• S

• No label; it no longer has N or S pole on the cut end.