A. because as the merry-go-round spins the child accelerates towards the center of the merry-go-round at a uniform rate.
When trying to describe how an object falls, Newton found that the speed of the object increased in every split second and no mathematics currently used to describe the object at any moment in time.
Answer:

Explanation:
When the block is displaced by x units
F= spring force
two springs are connected parallel

Writing Newtons second law, F = ma


a= x" ( differentiating x w.r.t time twice)

this the standard form of equation of oscillation spring mass system
This is the differential equation, x'' means that double differentiation of x , i.e, x'' is acceleration
since, Period 
therefore,

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Answer:
The work done by the friction force is 11700J
Explanation:
The work done by the friction force is given by:

According to Newton's second law:

So:
