Determination of resistivity of a wire using a micrometer, an ammeter, and a voltmeter

Question 1

how is area determined

Answer 1

micrometer

Question 2

how is the circuit set up

Answer 2

• ammeter is series
• voltmeter in parallel
• movable corcodile clips pressed firmuly on to the wire to minimise contact resistance
• use scale for length

Question 3

graph

Answer 3

resistance against length

R = V / I

Question 4

precautions

Answer 4

• low voltage used
  
  • although care should be taken to prevent short circuit