Current / Voltage Graphs: Answers

•The marks for each question appear in red boxes alongside the answer

V

I

-V

-I

Complete this graph to show the relationship between voltage and current for a filament lamp.

20 s

Question 1

V

I

-V

-I

Complete this graph to show the relationship between voltage and current for a filament lamp.

20 s

Question 1

2

I

V

-I

-V

Complete this graph to show the relationship between voltage and current for a diode.

Question 2

I

V

-I

-V

Complete this graph to show the relationship between voltage and current for a diode.

s

Question 2

2

Volt

ag

e

(V)

Current (A)

This graph shows the variation in voltage and current for a fixed resistor.

Calculate the resistance

1 2 43

108

6

4

2

Question 3

Volt

ag

e

(V)

Current (A)

Gradient = V/I

so gradient = resistance

Gradient = 8/2 = 4

So resistance = 4

1 2 43

108

6

4

2

1 min

Question 3

2

Cu

rren

t (m

A)

Voltage (V)

1 2 43

100

80

60

40

20

This graph shows the variation in voltage and current for a fixed resistor.

Calculate the resistance

Question 4

Cu

rren

t (m

A)

Voltage (V)

1 2 43

100

80

60

40

20

Gradient = I / V

so Gradient = 1/resistance

Gradient = 0.06/4.5 (current in mA)

= 0.013333

1.5 min

Question 4

So resistance = 1/ 0.01333

resistance = 75 4

Which circuit best allows you to determine

Current / Voltage relationships

A B

Question 5

Circuit B, because it allows you to apply voltages right down to 0V

B

Question 5

1

Will this diode conduct or not ?

10 s

Question 6

Yes, it is said to be forward biased.

1

Which bulbs will light ?

Question 7

Only bulb C will light.

1

Write down the Ohm’s Law Equation.

Question 8

V = IR1

This bulb has a resistance of 2

Calculate the reading on the ammeter. 9V

Question 9

V = IR

so I = V/R

I = 9/2

I = 4.5 A 9V

Question 9

2

When current enters at ‘A’ it leaves at ____

When current leaves at ‘A’ it entered at ____

When current enters at ‘B’ it leaves at ____

When current leaves at ‘B’ it entered at ____

Question 10

C

D

C

D

4

End Of Answers

Add up your total out of... 20