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To find momentums we need the speeds before and after collision. The simplest way to find these speeds is to use the energy conservation law.

Before falling a ball had only potential energy `mgh_1.￼` Just before collision it had only kinetic energy `mV_1^2/2, ` ￼ and they was equal. Therefore ￼`V_1=sqrt(2gh_1),`...

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Hello!

To find momentums we need the speeds before and after collision. The simplest way to find these speeds is to use the energy conservation law.

Before falling a ball had only potential energy `mgh_1.￼` Just before collision it had only kinetic energy `mV_1^2/2, ` ￼ and they was equal. Therefore ￼`V_1=sqrt(2gh_1),` where `￼h_1=3m.`

The same consideration gives that the speed after the collision is `V_2=sqrt(2gh_2)` ,￼ where `￼h_2=2m. ` Now we can answer (1) and (3).

(1) the momentum before collision is `mV_1 approx 0.61((kg*m)/s)` and after is ￼`mV_2 approx 0.50((kg*m)/s).`

(3) note that impulse is a vector, it has the same direction as velocity. The momentum before collision is directed downwards and after -- upwards. So the difference of moments is the sum of their magnitudes, i.e. `1.11 kg*m/s.`

For (2) we have to know that a force may be expressed as the derivative of a momentum (Newton's Second law, actually). Therefore the integral of a force is the difference of momentums. And the average force is this difference divided by a time. Force is upwards all the time.

(2) average force is ￼`(1.11)/(5*10^(-3)) approx 222(N).`