6V

Voltage

(V)

Current

(A)

0 0.00

0.1

0.25

0.5

1.0

1.5

2.0

2.5

3.0

3.5

4.0

4.5

5.0

5.5

6.0

Your teacher will show you how to build this circuit.

Copy the table into your

book. Adjust the voltage

to each of the values

shown, and record the

current in the table.

6V

Voltage

(V)

Current

(A)

0 0.00

0.1

0.25

0.5

1.0

1.5

2.0

2.5

3.0

3.5

4.0

4.5

5.0

5.5

6.0

Now replace the bulb with a 22Ω resistor

Add another column to

your table to record the

current through the

resistor at the same

voltages.22Ω

1. Plot a graph of current against voltage for both components.

- plot both sets of data on the same graph

- use a sheet of A4 graph paper in a landscape orientation

- make sure current is on the y-axis and voltage is on the x-axis

2. Look at the values of current for both the bulb and resistor when the voltage is 1V. Which component has the higher resistance at this applied voltage? Explain your answer!!!

3. What happens to the resistance of the bulb as the voltage is increased? Once again you must explain your answer.

4. At what voltage do the resistance of the bulb and the resistor become equal? Explain how you were able to tell.

Your teacher will show you how to use Ohm’s Law to calculate the resistance of the bulb at various points on the graph. Use this principle to answer these questions:

1. What is the resistance of the bulb when:a) The voltage is 2.5Vb) The voltage is 5Vc) The current is 0.15A

2. A bulb has a resistance of 12.5Ω. What current will flow through the bulb when a voltage of 20V is applied?

4. Another bulb is rated as having a resistance 12Ω when the current is 0.6A. What voltage is required to produce this current?