(a) The compression of the spring is 7.4 cm.
(b) When the object comes to rest its potential energy from the given height will be converted into elastic potential energy of the spring.
The compression of the spring is calculated by applying Hooke's law as follows;
F = kx
x = F/k
x = (mg)/k
x = (3 x 9.8)/400
x = 0.074 m
x = 7.4 cm
When the object comes to rest its potential energy from the given height will be converted into elastic potential energy of the spring.
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