What Is the Stretch of a Cable Under Load?

[verisimilitude]

Homework Statement

A 1.25m diameter wrecking ball hangs motionless from a 1.75 cm diameter cable. The wrecking ball is solid and is constructed of steel (density = 7800 kg/m3). If the cable is 16 m long, how much does the cable stretch? For the cable use E = 175 GPa.

Homework Equations

δ=(FL/AE)

The Attempt at a Solution

δ=(FL/AE)

F=ρ*v*g
=7800*(4/3)*pi*r^3*9.8
=78171.66 N

A=PI*R*R
=(pi*(1.75*1.75)/4)*10^-4
=2.4*10^-4

E=175000 N-m^2

L=16 m

When I plug in the values I get 29779.68 m which I know cannot be correct.

Thanks for your time

 

[voko]

Look up what G in GPa signifies.

 

[verisimilitude]

I've been working on this problem for 3 hours now because I failed to realize my simple mistake. Thank you a lot.