Question

1. A student decides to investigate the relationship between the type of conductor and current strength. A 200 mm length of nichrome wire with a diameter of 0,3 mm is wound into a coil and attached to the circuit. The potential difference is measured across the coil for 5 different currents. The experiment is repeated for a 200 mm length of copper wire with a diameter of 0,3 mm. The following results are obtained: 0,2 0,4 0,6 0,8 1,0 Current through each wire (A) Potential difference across the nichrome wire (V) Potential difference across the copper wire (V) 0,8 1,6 2,4 3,2 4,0 0,4 0,8 1,2 1,6 2,0
1.1 Why must the resistance wires used for this investigation be the same length? (1)
1.2 Which resistance wire (nichrome or copper) has the greatest resistance? Explain your answer. (2)​

Answer 1

Answer:

1.1) so that the surface area remains constant and the experiment remains fair.

1.2) Copper is metal whereas nichrome is an alloy.The Resistivity of an alloy is greater than the resistivity of a metal.Hence,the resistance of nichrome is greater than that of copper.