Numericals from Class XI Physics Conservation of Momentum)

  1. A 41.0-kg boy, riding a 1.60-kg skateboard at a velocity of 5.70 m/s across a level sidewalk, jumps forward to leap over a wall. Just after leaving contact with the board, the boy’s velocity relative to the sidewalk is 6.00 m/s, 9.30° above the horizontal. Ignore any friction between the skateboard and the sidewalk. What is the skateboard’s velocity relative to the sidewalk at this instant?
  2. A 1.20-g bullet, traveling at a speed of 478 m/s, strikes the wooden block of a ballistic pendulum. The block has a mass of 191 g. (a) Find the speed of the bullet/block combination immediately after the collision. (b) How high does the combination rise above its initial position?
  3. After skiding down a snow-covered hill on an inner tube, Ashley is coasting across a level snowfield at a constant velocity of +3.0 m/s. Miranda runs after her at a velocity of +4.2 m/s and hops on the inner tube. How fast do the two of them slide across the snow together on the inner tube? Ashley’s mass is 71 kg, and Miranda’s is 58 kg. Ignore the mass of the inner tube and any friction between the inner tube and the snow.
  4. A car (mass = 1170 kg) is traveling at 28.8 m/s when it collides head-on with a sport utility vehicle (mass = 2580 kg) traveling in the opposite direction. In the collision, the two vehicles come to a halt. At what speed was the sport utility vehicle traveling?
  5. In an Atwood system mass 1= 2 kg and mass 2=7kg. The masses of the pulley and strings are negligible by comparison, the pulley turns without friction and the string does not stretch. The lighter object is released with a sharp push that sets into motion at v(initial)= 2.4 m/s downward.
    How far will m1 descend below it’s initial level?
    Find the velocity of m1 after 1.8 seconds

Comments

  1. anjana roshan says:

    dear sir!
    i have seen at the petroleum cooperation, before feeling the fuel in to bowser tank, they connect the earth wire and ground the tank of it.
    why do they ground the tank?
    is there a something related with eddy current?

    1. admin says:

      This is not for eddy current but STATIC ELECTRICITY. The vehicle might have acquired some static charges on its body while in motion and this must be earthed (grounded) so as to avoid any mishap caused by static discharge (sparks) which would be sufficient to burn the entire surroundings.