Answer:
R' = 4R
The resistance will become 4 times the initial value.
Explanation:
The resistance of a wire at room temperature, is given by the following formula:
R = ĻL/A Ā ----------- equation 1
where,
R = Resistance of wire
Ļ = resistivity of the material
L = Length of wire
A = Cross-sectional area of wire
Now, if the length (L) is multiplied by 4, then resistance will become:
R' = Ļ(4L)/A
R' = 4 (ĻL/A)
using equation 1:
R' = 4R
The resistance will become 4 times the initial value.
