Question

In: Physics

A child pushes a merry-go-round that has a diameter of 4.00 m and goes from rest...

A child pushes a merry-go-round that has a diameter of 4.00 m and goes from rest to an angular speed of 18.0 rpm in a time of 47.0 s.

1) Calculate the average angular acceleration of the merry-go-round. (Express your answer to three significant figures.)

2) Calculate the angular displacement of the merry-go-round. (Express your answer to three significant figures.)

Solutions

Expert Solution

Initial angular speed of the merry-go-round = 1 = 0 rad/s (At rest)

Final rotational speed of the merry-go-round = N2 = 18 rpm

Final angular speed of the merry-go-round = 2

2 = 1.885 rad/s

Time period = T = 47 sec

Average angular acceleration of the merry-go-round =

2 = 1 + T

1.885 = 0 + (47)

= 4.01 x 10-2 rad/s2

Angular displacement of the merry-go-round =

= 1T + T2/2

= (0)(47) + (4.01x10-2)(47)2/2

= 44.3 rad

1) Average angular acceleration of the merry-go-round = 4.01 x 10-2 rad/s2

2) Angular displacement of the merry-go-round = 44.3 rad


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