phy1020.DVI

Solution.From the above table, for copper,YD 117  109 N/m^2 andD0:355. From Eq. (5.25), we
have

GD

Y

2.1C/

D

117  109 N=m^2

2.1C0:355/

D43:2 109 N=m^2

And the spring constant is found from Eq. (5.24)

kD

Gd^4

8ND^3

D

.43:2 109 N=m^2 /.10^3 m/^4

8.50/.10^2 m/^3

D 108 N=m