Four pieces of constantan wire, marked E, F, G, and H, each of length 1.0m, are at the temperature. Their respective diameters are 1 mm, 2 mm, 6 mm, and 10 mm. Which wire has the highest resistance?
A
E
B
F
C
G
D
H
Verified Correct Answer: A.
Physical Principles & Numerical Solution
Using the equation, R = \(\frac{\rho l}{A}\)
we conclude that the wire with the smallest diameter will have the highest resistance i.e. wire E
Source: WAEC / JAMB / NECO Classroom Archive (Record #72073)