Resistivity

Question 1

Greater voltage

Answer 1

Greater current

Question 2

What happens if the variable resistor isn’t there

Answer 2

The wire provides some resistance
But have a very very large current
Due to its small resistance

This is why you have it series with a variable resistor
Because if current is too high the wire could overheat, melt or burn yourself

Question 3

Why use resistor

Answer 3

Maintain a low safe wire

Resistivity is affected by temperature a bit

Question 4

Switch off between measurements

Answer 4

Gives wire chance to cool down

So stops it overheating

Question 5

Graph

Answer 5

Straight line of best fit
Resistance proportional to length
The constant is p x A

R:y
L:x

Question 6

How do you measure cross sectional area

Answer 6

Measure diameter with micrometer