- #1

kalupahana

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## Homework Statement

A meri go round is rotating it vertical axis through center with a diameter 4.5m. It's moment of inertia is 1750 kg m

^{2}and angular velocity is 0.70 rad/s. 4 men with mass 65 kg instantly enter the the edge of the meri go round. Calculate the angular velocity of meri go round after that instant.

## Homework Equations

Conservation of angular momentum

**I**

_{1}ω_{1}= I_{2}ω_{2}I = ma

^{2}

## The Attempt at a Solution

I

_{1}= 1750 kg m

^{2}

ω

_{1}= 0.70 rad/s

The mass of meri go round

1750 = ma

^{2}

1750 = m(4.5/2)

^{2}

(1750 x 4)/ (4.5)

^{2}= m

The mass of meri go round after 4 men get in

m = (1750 x 4)/ (4.5)

^{2}+ 65 x 4

m = [7000 + (260 x (4.5)

^{2}]/(4.5)

^{2}

m = 12265/(4.5)

^{2}

Then

I

_{2}= 12265 kg m

^{2}

Applying conservation of angular momentum

1750 x 0.70 = 12265 ω

_{2}

ω

_{2}= 1.099 rad/sBut the answer is given as

**0.004**rad/s.

Please help me to reach to this answer