RP: Resistance

Question 1

how could you investigate the effect of different lengths of a wire on resistance

Answer 1

set up this circuit:

————-I1————————-
l l
l l
—A—– resistance wire——
l l
————–V————-
connect a crocodile clip from one side of the ammeter using a crocodile clip to the resistance wire at 0 on the ruler
connect a lead from the battery to the resistance wire at 100cm using a crocodile clip. connect a voltmeter across the resistance wire.
set the voltage on the power pack to 4V,switch on quuickly and record ammeter and voltmeter readings
shorten the length of the resisitance wire by moving the 100cm crocodile clio to 95cm. keep repeating this to obtain 10 readings from different parts of the ruler
calculate and record the resistance for each length

Question 2

what is a hazard for this experiment?

Answer 2

the wire can get hot and burn you so make sure you switch the power pack off in between readings