P4

Question 1

What is the equation for potential difference?

Answer 1

V = IR

Question 2

What is the equation for resistance?

Answer 2

R = V/I

Question 3

What is potential difference measured in?

Answer 3

Volts (V)

Question 4

What is resistance measured in?

Answer 4

Ohms

Question 5

What is Ohm’s law?

Answer 5

The current through a resistor at a constant temperature is directly proportional to the potential difference across the resistor.

Question 6

What is current measured in?

Answer 6

Amps (A)

Question 7

What is current presented as in equations?

Answer 7

I

Question 8

What is charge measured in?

Answer 8

Coulombs (C)

Question 9

What is the equation for current?

Answer 9

I = Q/t

Question 10

What is the equation for charge?

Answer 10

Q = It

Question 11

What does the t stand for in Q = It

Answer 11

Time (s)

Question 12

What is the current when 3C goes through a point in 2s?

Answer 12

1.5A

Question 13

What is the total charge when 10A flows for 15 seconds?

Answer 13

150C

Question 14

What is the resistance when a resistor is connected to a 9V battery which causes a 3A current to flow through the resistor.

Answer 14

3 Ohms

Question 15

What is the potential difference of a battery when a 10 Ohm resistor is connected with 9A flowing through it.

Answer 15

90V

Question 16

Can you describe the relationship of a graph for a resistor between V(V) and I(A)?

Answer 16

V is directly proportional to I which follows Ohm’s law

Question 17

Can you describe the relationship of a graph for a bulb between V(V) and I(A)?

Answer 17

V is not directly proportional to I so doesn’t follow Ohms law as the temperature increases

Question 18

What is the independent variable in an experiment?

Answer 18

The thing you change in order to test your hypotenuse.

Question 19

What is the dependent variable in an experiment?

Answer 19

The thing you measure in an experiment in order to see the effect of the IV

Question 20

What is the control variable in an experiment

Answer 20

The things you keep the same in an experiment in order to keep it a fair test.

Question 21

What is a thermistor?

Answer 21

A type of resistor that changes it’s electrical resistance with the temperature around the device

Question 22

What is an LDR

Answer 22

A semi-conductor whose resistance decreases as the intensity of light increases

Question 23

What is an LED?

Answer 23

A semi-conductor device which releases light as a current is passed through it

Question 24

What is a diode?

Answer 24

A type of device that only allows the current to flow in one direction

Question 25

Explain how a balloon can pick up a charge.

Answer 25

It can gather electrons from other objects giving the ballon a negative charge

Question 26

Explain how a balloon can stick to a wall.

Answer 26

Because the electrons in the wall will repel away creating a positive space in the wall where the negatively charged ballon will be attracted to