How much energy W needed to compress a spring from 15 cm to 10 cm if the constant of the spring is 150 N/m.

Answer 1

d = 15-10 = 5 cm = 0.05 m.

F = 150N/m * 0.05m = 7.5 N.

Work = F*d = 7.5 * 0.05 = 0.375 Joules.

Answer 2

10-15=-5cm=-0.05m
0.5*150*(-0.05)^2=0.1875J

Answer 3

∆L=L¹ - L²
= 15cm - 10cm
= 5cm
= 0.05m
F= 150N X 0.05m
= 7.5N
W = FD
=7.5N X 0.05m
=0.375J