Required Practical: Resistance

Question 1

How can you control the length of the wire?

Answer 1

measure it with a ruler and only connect a section of it that is a measured length with crocodile clips

Question 1

Objective =

Answer 1

measuring the resistance of a wire - according to its length

Question 2

in order to be able to use the equation R = V/I to find resistance,t he circuit must have…

Answer 2

ammeter

voltmeter

Question 3

Problems that may arise: zero error

Answer 3

1. Zero error - sometimes on the graph it may say that even though the wire length is zero there is some resistance. This is to do with an error with the measuring instrument.

Question 4

Problems that may arise: resistance caused by the contact between…

Answer 4

the crocodile clip and the wire

Question 5

Problems that may arise: Heating Effects

Answer 5

If the temperature of the wire increases, then the resistance will also increase - use a low potential difference which keeps the current low and reduces the heating of the wire.

OR

Only turn on the current when taking a reading. Turn off the current between readings.