A laboratory spool contains of uniform nichrome wire whose circular cross-sectional…
PHYSICS · Multi-part · CBSE · Physics · Current Electricity · Current Electricity
Problem
A laboratory spool contains 7.5m of uniform nichrome wire whose circular cross-sectional diameter is 0.30mm. The resistivity of nichrome at room temperature is 1.1×10−6Ω⋅m.
(a) Determine the resistance of the entire length of wire on the spool. Show all steps in your calculation and include units.
(b) The wire is connected across the terminals of a variable power supply. What potential difference must the supply deliver to establish a steady current of 1.8A in the wire?
(c) State the unit that best expresses the answer obtained in part (b) and explain why that unit is appropriate for the physical quantity involved.