A wire of cross-sectional area 0.60mm2 has a resistivity of 7.2 x 10-7 Ω. Calculate the length of wire that will have a resistance of 3Ω.

by | Jan 25 | Physics WAEC | 0 comments

A. 0.25m
B. 2.50m
C. 3.60m
D. 36.00

Correct Answer: Option B

B. 2.50m

Explanation

R = P/LA

C = R/AP

C = 0.60×10−6×3/7.2×10−7

C = 2.50m

Users Also Read These:

Copyright warnings! Do not copy.