Problema Solution
Kindly help me solve this problem:
Inverse Proportion
The resistance R of a wire of a constant length is inversely proportional to the square of its diameter d. If the resistance of a wire 2 mm in diameter is 25 ohms, find
a) an equation connecting the resistance of the wire, R, to the diameter of the wire,d.
b) the resistance of a wire with diameter 2.5 mm
c) the diameter of a wire with a resistance of 15 ohms.
Answer provided by our tutors
R = k/d2
R=25 , d=2
25 = k / 4
k=100
a) Equation : R = 100/d2
b) R = 100/2.52 = 16
c) 15 = 100/d2
d = sqrt ( 100/15) = 2.58 mm