Question

two bodies of mass 3kg and 4 kg respectively are acted upon by 10N of force.what is the change in momentum if force acts for 2 seconds?

Answer 1

Question #30155

two bodies of mass 3kg and 4 kg respectively are acted upon by 10N of force. what is the change in momentum if force acts for 2 seconds?

Solution:

The momentum (change in momentum) of the body is:

$$P = m v, \text{ were } m \text{ is the mass } v \text{ is the velocity of the body}$$

The velocity on equally accelerated motion is:

$$v = a t \text{ were } a \text{ is the acceleration}$$

According to the second Newton's law:

$$a = \frac{F}{m} \text{ were } F \text{ is the force}$$ $$= >$$ $$P = m * \frac{F}{m} * t$$ $$= >$$ $$P = F t, \text{ were } F \text{ is the force } t \text{ is the time of force acting.}$$ $$P = 10 * 2 = 20 \, \text{Kgmsec}^{-1}$$

Answer: the change in momentum of each body is $20 \, \text{Kgmsec}^{-1}$.