Static Electricity

Question 1

Name 2 ways something can become charged:

Answer 1

• Friction
• Induction

Question 2

What is the difference between a conductor and an insulator?

Answer 2

In conductors the electrons are free to move, but in insulators the electrons are not.

Question 3

How does lightning work?

Answer 3

Water droplets/ice crystals rub against each other. Charge builds up and the lightning spark means the cloud is discharging.

Question 4

What effect do charged objects have on each other?

Answer 4

Positive and negative charged objects attract or pull each other together, while similar charged objects (2 positives or 2 negatives) repel or push each other apart.

Question 5

How do you charge an object by friction?

Answer 5

When objects are rubbed together, friction transfers electrons between them. Objects losing electrons become positively charged, while objects gaining electrons become negatively charged.

Question 6

How do you charge an object by induction?

Answer 6

Induction is a way to charge an object without touching it. It is done by bringing a charged object near a neutral conductor, which results in the movement of the opposite charges of the charged object to the other side of the conductor. This creates an unbalance in the distribution of charges on the conductor.

Question 7

What are the dangers of static electricity?

Answer 7

• Sparks can occur when objects become charged
• Lightning is an example of discharge
• sparks can cause fires or explosions

Question 8

How can we refuel a plane safely?

Answer 8

A build up of static charge could cause an explosion. This can be prevented by joining the delivery tanker and the fuel tank electrically with a metal wire. The wire provides a path for electrons to flow along, and prevents the buildup of any dangerous static electricity. This is called earthing.

Question 9

How does electrostatic spray painting work?

Answer 9

When the paint leaves the nozzle of the paint gun, it is given a positive charge and the metal is given a negative charge. This is so when the paint leaves the gun, it repels the metal and evenly distributed over the surface, giving an even layer of paint. Opposite charges attract, so the paint sticks and there is less paint wasted.