Home
Class 11
PHYSICS
A 250 g ball moving horizontally with ve...

A 250 g ball moving horizontally with velocity 10.0m/s strikes inclined surface of a 720g smooth wedge as shown in the figure. The wedge is placed at rest on a frictionless horizontal ground. If the coefficient of restitution is 0.8, calculate the velocity of the wedge after the impact.

Text Solution

Verified by Experts

Let us consider the ball as the body A and the wedge as the body B. Before collision let velocity of ball is u^a after the impact, the ball bounces with velocity `v_(A)` and the wedge advances in horizontal direction with velocity `v_(B)`. These velocities and their t and n-components are immediately before and after the impact are shown in the following figures.

Component along t-axis The ball is free to move before and after the impact, therefore its t-component of momentum conserved. hence, t-component of velocities of the ball remains unchanged.
`v_(At)=U_(At)=10cos37.=8m//s` ...(i)
Momentum Conservation In the horizontal direction, there is no extrnal force on both the bodies. Therefore horizontal component of total momentum of both the bodies remain conserved. `m_(A) u_(A) = m_(A)(v_(At)cos37. -v_(An) cos53.) +m_Bv_(B)`
`0.25xx10=0.25(8xx4/5-(3v_(An))/5)+0.72v_B`
Coefficient of restitution Concept of coefficient of restitution e is applicable only for the n-component velocities.
`v_(Bn)-v_(An)=e(u_An-U_Bn)rarr 3v_B/5-v_An=0.8(6-0)` ...(iii)
From equations (i), (ii) and (iii), we obtain `v_(B) = 2.0 m//s`
Doubtnut Promotions Banner Mobile Dark
|

Topper's Solved these Questions

  • CENTRE OF MASS

    ALLEN |Exercise EXERCISE-I|40 Videos
  • CENTRE OF MASS

    ALLEN |Exercise EXERCISE-II|43 Videos
  • BASIC MATHEMATICS USED IN PHYSICS &VECTORS

    ALLEN |Exercise EXERCISE-IV ASSERTION & REASON|11 Videos
  • ELASTICITY, SURFACE TENSION AND FLUID MECHANICS

    ALLEN |Exercise Exercise 5 B (Integer Type Questions)|3 Videos

Similar Questions

Explore conceptually related problems

A ball of mass m=1kg falling vertically with a velocity v_0=2m//s strikes a wedge of mass M=2kg kept on a smooth, horizontal surface as shown in figure. If impulse between ball and wedge during collision is J. Then make two equations which relate J with velocity components of wedge and ball. Also find impulse on wedges from ground during impact.

A block of mass m is place on a sm ooth inclined wedge ABC of inclination 0 as shown in figure. The wedge is given an acceleration ‘a’ towards the right. The relation between a and theta for the block to rem ain stationary on the wedge is

Knowledge Check

  • A ball moving with velocity 2m/s collides head on with another stationary ball of double the mass . If coefficient of restitution is 0.5 then their velocities after collision will be ………. ms^(-1) .

    A
    0,1
    B
    1,1
    C
    `1,0.05`
    D
    0,2
  • Similar Questions

    Explore conceptually related problems

    A smooth sphere is moving on a horizontal surface with velocity vector 3hat(i) + hat(j) immediately before it hits a vertical wall. The wall is parallel to the vector hat(j) and the coefficient of restitution between the wall and sphere is (1)/(3) . The velocity vector of the sphere after it hits the wall is :-

    A disk sliding with velocity u on a smooth horizontal plane strikes another identical disk kept at rest as shown in the figure. If the impact between the disks is perfectly elastic impact, find velocities of the disks after the impact.

    A bullet of mass 10g travelling horizontally with a velocity of 10 ms(-1) ? strikes a bag filled with sand and penetrate 5 m insides and comes to rest, then ( 1 ) Calculate the resistant force on the bullet by the bag Alled with sand. (2) Calculate the time for the bullet to come to rest.

    A 100gm ball moving horizontally with 20m/s is struck by a bat, as a result it starts moving with a speed of 35m/s at an angle of 37 above the horizontal in the same verticle plane as shown in the figure. ltb/rgt (a) Find the average force exerted by the bat if duration of impact is 0.30s.ltb/rgt (b) FInd the average force exerted by the bat if duration of impact is 0.03s. (c) Find the average force exerted by the bat if duration of impact is 0.003s. (d) What do you conclude for impulse of weight of the ball as duration of contact decreases?

    What is the value of the force vecF to be applied horizontally on a block of mass 5 kg which is in contact with a wall, as shown in the figure. (Take g = 10 m//s^(2) ) such that it does not fall down. The coefficient of friction between the block and the wall is 0.4.

    A ball of mass 2 kg is moving with velocity 20 m/sec strikes with the surface and rebounds with same speed, if time of contact is 0.1 sec then calculate average force on the ball.

    A 150 g ball, moving horizontally at 20m/s was hit straight back to bowler at 12m/s. If contact with bat lasted for 0.04 sec, then average force exerted by the bat on the ball is:-