Sign in
12thPass logo
New chatPYQ LibraryDoubtsRank report
Sign in to see Recents

Your guest activity stays on this device

Sign in to save progress →
Sign in

Center of Mass and Collision question

2008 · Q155
Guest · filters and generic practice availableBrowsing as a guest · PYQ filters and generic practice are available. Sign in only for personalised features and saved progress.
  1. PYQ Library
  2. /NEET
  3. /Physics
  4. /Center of Mass and Collision
  5. /2008 · Q155

Center of Mass and Collision question

2008 · Q155

NEETPhysicsCenter of Mass and CollisionMCQ+4 / −1
A shell of mass 200 gm is ejected from a gun of mass 4 kg by an explosion that generates 1.05 kJ of energy. The initial velocity of the shell is :
  1. A
    40 ms−-−1
  2. B
    120 ms−-−1
  3. C
    100 ms−-−1
  4. D
    80 ms−-−1
View written solutionFree

Correct answer: C

As per laws of conservation of momentum and energy, if v and V represents initial velocity of shell of mass m and recoil velocity of gun of mass M respectively, then

mv + MV = 0

V=−(mM)vV = - \left( {{m \over M}} \right)vV=−(Mm​)v

=−(0.24)v=−v20m/s = - \left( {{{0.2} \over 4}} \right)v = - {v \over {20}}m/s=−(40.2​)v=−20v​m/s

Here (–) sign shows that recoil velocity of gun is opposite to velocity of shell.

The energy of explosion is used to impart kinetic energy to shell and gun so that we have

12{1 \over 2}21​ (mv2 + MV2) = 1.05 × 103

12{1 \over 2}21​ [0.2v2

  • (4v2 / 400)] = 1.05 ×103

    ⇒\Rightarrow⇒ v2 = 104

    ⇒\Rightarrow⇒ v = 100 m/s
PreviousNext

More from Center of Mass and Collision

  • A 0.5 kg ball moving with a speed of 12 m/s strikes a hand wall at an angle of 30o with the wall. It is reflected with the same speed at the same angle. If the ball is in contact with the wall for 0.25 seconds, the average force acting on…2006 · MCQ
  • A bomb of mass 30 kg at rest explodes into two pieces of masses 18 kg and 12 kg. The velocity of 18 kg mass is 6 m s−1. The kinetic energy of the other mass is :2005 · MCQ
  • Consider a system of two particles having masses m1 and m2. If the particle of mass m1 is pushed towards the mass centre of particles through a distance d. by what distance would be particle of mass m2 move so as to keep the mass centre of…2004 · MCQ
  • A stationary particle explodes into two particles of masses m1 and m2 which move in opposite directions with velocities v1 and v2. The ratio of their kinetic energies E1/E2 is :2003 · MCQ
  • If kinetic energy of a body is increased by 300% then percentage change in momentum will be :2002 · MCQ
  • A rod of length is 3 m and its mass acting per unit length is directly proportional to distance x from one of its end then its centre of gravity from that end will be at :2002 · MCQ
  • A disc is rolling, the velocity of its centre of mass is vcm. Which one will be correct?2001 · MCQ
  • A ball of mass 0.5 kg is dropped from a height of 40 m . The ball hits the ground and rises to a height of 10 m . The impulse imparted to the ball during its collision with the ground is (Take g=9.8 m/s2 )2025 · MCQ