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## Homework Statement

In the figure below, a 30 kg child stands on the edge of a stationary merry-go-round of mass 100 kg and radius 2.0 m. The rotational inertia of the merry-go-round about its rotation axis is 150 kg·m2. The child catches a ball of mass 1.1 kg thrown by a friend. Just before the ball is caught, it has a horizontal velocity v of magnitude 11 m/s, at angle ϕ = 37° with a line tangent to the outer edge of the merry-go-round, as shown. What is the angular speed of the merry-go-round just after the ball is caught?

## Homework Equations

p = mv

L = Iw

## The Attempt at a Solution

So I'm assuming that angular momentum is conserved. Thus,

mv = Iw

I found the total I.

I_merrygoaround = 150

I_child = MR^2 = 120

I_ball = MR^2 = 1.1(rsin(phi))^2 = 1.44

I_total = 271.44

[tex]\omega[/tex] = (mv) / (I_total) = 12.1/271.44 = 0.0445 rad/s

But this is incorrect.

What did I do wrong?