Home
Class 11
PHYSICS
A ping-pong ball of mass m is floating i...

A ping-pong ball of mass `m` is floating in air by a jet of water emerging out of a nozzle. If the water strikes the ping-pong ball with a speed `v` and just after collision water falls dead, the mass flow rate of water in the nozzle is equal to :

A

`(2mg)/(v)`

B

`(mv)/(g)`

C

`(mg)/(v)`

D

None of these

Text Solution

Verified by Experts

The impact force `F=(Deltap//Deltat)`, where `Deltap=` change of momentum of water of mass `Deltam` striking the ball with a speed `v` during time `Delta t`. Since water falls dead after collision with the ping-pong ball
`Deltap=DeltamvrArrF=v(Deltam)/(Deltat)`
where `(Deltam)/(Deltat)=` rate of flow of water in the nozzle.
Since the ball is in equilibrium
`F-mg=0rArrF=mg`
`rArr(vDeltam)/(Deltat)=mg`
`rArr(Deltam)/(Deltat)=(mg)/(v)`
Promotional Banner

Topper's Solved these Questions

  • ELASTICITY & WAVES

    FIITJEE|Exercise Example|16 Videos

Similar Questions

Explore conceptually related problems

A ping-pong ball of mass m is floating in air by a jet of water emerging out of a nozzle. If the water strikes the ping-gong ball with a speed v and just after collision water falls dead, the rate of flow of water in the nozzle is equal to

A ball of mass 100g moving at a speed of 12 m s^(-1) strikes another ball of mass 200 g at rest. After the collision both the balls move with a common velocity. Find the common velocity.

A small ball of mass m collides with as rough wal having coeficient of friction mu at an angle theta with the normal to the wall. If after collision the ball moves wilth angle alpha with the normal to the wall and the coefficient of restitution is e , then find the reflected velocity v of the ball just after collision.

If a small ping pong ball is placed in a vertical jet of water or air, it will rise to a certain geight above the nozzle and will be spinning there.

A ping-pong ball strikes a wall with a velocity of 10 ms^(-1) . If the collision is perfectly elastic, find the velocity if ball after impact

A ball of mass m moving with a velocity v undergoes an oblique elastic collision with another ball of the same mass m but at rest. After the collision if the two balls move with the same speeds , the angle between their directions of motion will be:

A stream of water flowing horizontally with a speed of 15 m/s gushes out of a tube of cross sectional area 10^(-2)m^(2) and hits at a vertical wall and after collision falls dead. The force exerted on the wall by the impact of water is