10 Electricity And Circuits

Question 1

What is electrical current?

Answer 1

Electrical current is the flow (movement) of electric charges.

Question 2

What is current measured in?

Answer 2

Amperes (A)

Question 3

Does the value of current change?

Answer 3

Current has the same value at any point in a single closed loop.

Question 4

How do you calculate the flow of charge?

Answer 4

The flow of charge (C) = current (A) x time (s).

Question 5

What is the symbol equation fo charge?

Answer 5

Q = I x t

Question 6

What is an electrical conductor?

Answer 6

Material allowing electric currents to pass through it

Question 7

What is an example of an electrical conductor?

Answer 7

All metals

Question 8

What is an electrical insulator?

Answer 8

A material that doesn’t allow electric currents to pass through it

Question 9

What are examples of electrical insulators?

Answer 9

Plastic

Glass

Question 10

Why can electrical conductors conduct electricity?

Answer 10

Free electrons

- current is the flow of these free electrons

Question 11

Why does an electrical insulator not conduct electricity

Answer 11

No free electrons

- no charges free to carry current

Question 12

What is potential difference?

Answer 12

difference in the amount of energy that charge carriers have between two points in a circuit

Energy transferred by unit charge passed

Question 13

What is potential difference measured in?

Answer 13

Volts (V)

Question 14

What instrument do you use to measure a potential difference?

Answer 14

A voltmeter

Question 15

What is the potential difference equation?

Answer 15

V = E/Q

Voltage = energy / charge

Question 16

What does an ammeter measure?

Answer 16

flow of current that passes through it.

Question 17

How do ammeters have to be connected?

Answer 17

In series (in the same loop of the circuit) with the electrical component whose current you are measuring

Question 18

What do voltmeters measure?

Answer 18

Potential difference between two points in a circuit.

Question 19

How must voltmeters be connected?

Answer 19

parallel (on a separate branch of the circuit) with the two points being measured.

Question 20

Why is potential difference measured between two points either side of a component?

Answer 20

P.d is the energy used between two points in a circuit

Question 21

How is current measured?

Answer 21

Ammeter

Through a component

Question 22

What is a potential difference of 1 volt equal to?

Answer 22

1 joule of energy being used by one coulomb of charge when it flows between two points in a circuit.