Question

Give reasons:

A)When a bus takes a U-turn,passengers sitting inside are thrown a side.

B)It is easier to stop a tennis ball than a cricket ball moving with the samespeed.

C)A passenger jumping out of a rapidly moving bus falls forward with his face downwards.

D)A person sitting in bus falls forward when moving bus suddenly stops and people sitting in bus fall backward when bus suddenly starts.

Answer 1

It’s because of inertia, which is simply the tendency of any body to continue on whatever path it’s travelling unless acted on by an external force. For a standing passenger, his/her body will tend to continue along the straight line route the bus was travelling before the sharp turn. As the passenger’s feet are fairly firmly located to the floor of the bus when it turns, a force will act upon the passenger’s feet accelerating them towards the centre of the turn



Tennis ball is lighter in weight as compare to cricket ball and thus has momentum much less than the momentum of cricket ball ( momentum is equal to mass ×
velocity)
body that has large momentum possesses large impact as well thus cricket ball having more momentum than tennis ball even if they move with same velocities causes more impact on the hands of person that tends to catch it and might sometimes get hurt thus it is easy to catch a tennis ball because its momentum is less n so is its impact




when the person is in the bus its whole body is in a state of motion. When he suddenly jumps off the bus and stands on the road, the lower part of his body suddenly comes to rest while the upper part is still in motion(forward i.e the direction of bus). As such upper body moves forward while the lower body is at rest. Hence the passenger fall forward (but it won't happen if he runs in the direction of the bus).

• So when the bus or train stopped suddenly, a passenger sits inside tends to fall forward. Because the lower part of the body comes to rest with the bus while the upper part tends to continue its motion due to inertia.
• The reverse happened when the bus or train started suddenly, then that time our body fall backward because lower body stick with the bus so it goes forward while the upper part tries to remain in rest due to inertia of rest.