Question

A wire is stretched to a certain amount under a load. If the load and diameter of the wire are both increased to three

times of their initial value, find the stretch caused in the wire.​

Answer 1

Answer:

Young's modulus, Y=

A

W

×

l

L

∴ Elongation, l=

AY

WL

=

πr

2

Y

When both load and radius are increased to four times, the elongation becomes

l

′

=

π(4r)

2

Y

4W×L

=

4πr

2

Y

WL

=

4

l