A trolley is moving with a velocity of 20 meter per second. The mass of the trolley 100.8 kg and Apple mass of 0.2 kg is moving with a velocity of 5 km/s. The apple falls on the trolley. What is the final velocity of apple trolley together?
Refer to the diagram above.
Linear momentum will remain conserved along horizontal
so Pi=100.8∗20 kgm/s
Pf=(100.8+0.2)v kgm/s
By conservation of momentum,
Pi=Pf
2016=101v
v=2016/101=19.96 m/s.
If apple velocity is horizontal then result will be different.
In that case,
Pi=100.8∗20+0.2∗5000=3016 kg−m/s
and Pf=101v
and v=3016/101=29.8 m/s.