Investigating Resistance

Question 1

What’s the aim?

Answer 1

To investigate how the current flowing through a component is related to the voltage across the component.

Question 2

What’s the process for a resistor?

Answer 2

Choose a value for the resistance (R1, R2 or R3). Measure the current through the resistor over a range of voltages using an ammeter and a voltmeter. Record your results on a graph then repeat experiment for different values of the the resistance.

Question 3

What’s the process for a light bulb?

Answer 3

Measure the current through the resistor over a range of voltages. Plot your results on a graph.

Question 4

What’s special about diodes and light emitting diodes.

Answer 4

They only conduct a current in 1 direction and then only if the voltage applied exceeds a certain critical value.

Question 5

What’s the current for bulbs in series?

Answer 5

The same current flows through each bulb and the voltage across each bulb adds up to the total voltage.

Question 6

What’s the current for bulbs in parallel?

Answer 6

The voltage across each bulb is the same and the current through each bulb adds to the total current.