Electric and Magnetic Forces

Front

Why is a balloon attracted to hair when rubbed together?

Back

The balloon and the hair both have opposite charges

Front

Two bar magnets are held close together and released to move freely. Why do they quickly come together?

Back

The poles facing one another are opposite poles

Front

Why do paper clips move with a magnet placed beneath a table?

Back

Magnetic forces act at a distance, even between objects.

Front

Surrounding each magnet is an invisible force field called

Back

A magnetic field

Front

What is the relationship between the number of coils in an electromagnet and the strength of the magnetic field?

Back

The more coils an electromagnet has, the stronger the magnetic field.

Front

To decrease the strength of a magnetic field around an electromagnet, we must:

• increase the number of coils
• increase the size of the iron core
• decrease the size of the iron core
• decrease the number of coils

Back

decrease the number of coils

Front

What is the cause of electricity? (Think of John Travoltage!)
Options: Magnetism, Gravity, Moving electrons, Lightning

Back

Moving electrons

Front

The tool that used magnetic forces to show  which direction is north is _______.

Back

Compass

Front

A __________ is a particle with negative charge.

Back

Electron

Front

A negative charge and a positive charge will ________.

Back

Attract