Static Charges

Question 1

What is the equation for current?

Answer 1

Current = Charge / Time

Question 2

What is the symbol for current?

Answer 2

I

Question 3

What is the symbol for charge?

Answer 3

Q

Question 4

What is the unit of current?

Answer 4

Amps

Question 5

What is the unit of charge?

Answer 5

Coulombs

Question 6

What is the symbol equation for current?

Answer 6

I = Q / t

Question 7

How do you rearrange the current equation to find charge?

Answer 7

Q = I x t

Question 8

How do you rearrange the current equation to find time?

Answer 8

t = Q / I

Question 9

How do you build a static charge?

Answer 9

Rub two insulators together

Question 10

Explain how a static charge is built up in two objects rubbing together.

Answer 10

Friction transfers (negative) electrons

Question 11

I rub a piece of amber against a piece of cat fur. The cat fur gains a negative charge. What has happened?

Answer 11

Friction transfers electrons
Electrons are negative
Electrons have been transferred from the amber to the cat fur

Question 12

I rub a cloth against a plastic ruler and the ruler gains a positive charge. What has happened?

Answer 12

Friction transfers electrons
Electrons are negative
Electrons have been transferred from the ruler to the cloth

Question 13

I rub a balloon against some hair. The balloon has positive charge. What charge does the hair have?

Answer 13

Negative

Question 14

What direction on the field lines do the arrows point?

Answer 14

From positive to negative

Question 15

What type of field is around a spherical charge?

Answer 15

A RADIAL field

Question 16

Describe a radial field.

Answer 16

Straight lines going directly away from the centre.

Question 17

What is a danger of electrostatics?

Answer 17

In a petrol pump, when fluids flow, friction transfers electrons which builds a charge, which can cause a spark. Make it safe by GROUNDING the pump.