Electric Fields

Question 1

Describe the shuttling ball experiment

Answer 1

see textbook

Question 2

What is the gold leaf electroscope used for?

Answer 2

detecting charge

Question 3

Draw the electric fields of: two oppositely charged points, a point near a plate, and two oppositely charged plates:

Answer 3

see textbook

Question 4

What is the electric field strength?

Answer 4

the force per unit charge on a positive test charge placed at that point.

Question 5

What is electric potential?

Answer 5

work done per unit positive charge on a positive test charge when it is moved from infinity to that position.

Question 6

How do electric field strength and potential gradient compare?

Answer 6

electric field strength is the negative of the potential gradient.

Question 7

Define Coulomb’s law

Answer 7

force is proportional to the product of the charges. inversely proportional to the square of the separation.

Question 8

What is the change of potential equal to?

Answer 8

the area under an electric field strength against distance graph

Question 9

What are the main differences between gravitational fields and electric fields?

Answer 9

gravitational force is attractive only, whereas electric fields can be attractive and repulsive. Gravitational is between any two masses whereas electric is between any two charges.