Question

a boy of mass 20 kg is suspended vertically by means of a string of length 10 cm. the horizontal force required to pull the mass horizontally through 6 cm.

Answer 1

The force will be 117.6 N.

Explanation:  

If we consider string as spring then first we have to find the spring constant "K":

KL = mg  

K = mg/L  

K = (20)(9.8)/0.1 = 1960 Nm-1

Now, according to Hooke’s law:

F = K*x  

F = (1960)(0.06)

F = 117.6 N

Which is the required force to pull the mass horizontally through 6 cm.

Answer 2

Answer:

15 kg-wt

Explanation:

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