# Choose the correct option Column-I Column- II (A) Earth moving in an elliptical orbit  (only earth is system) (p) Conservation of linear momentum along any direction (B) A disc having translation and rotation motion both (both slipping on a rough surface (only disc in system) (q) Conservation of linear momentum along specific direction (C) A sphere rolling without slipping on a curved surface (only the sphere in system) (r) Conversion of angular momentum about any point in the space (D) Projection of a particle from the surface of earth (only particle in system) (s) Conversion of angular momentum about a specific point in the space CODES :   A B C D     a) B d c a     b) c,d b,a d a     c) d b a c     d) c d does not m d

## Question ID - 101083 :- Choose the correct option Column-I Column- II (A) Earth moving in an elliptical orbit  (only earth is system) (p) Conservation of linear momentum along any direction (B) A disc having translation and rotation motion both (both slipping on a rough surface (only disc in system) (q) Conservation of linear momentum along specific direction (C) A sphere rolling without slipping on a curved surface (only the sphere in system) (r) Conversion of angular momentum about any point in the space (D) Projection of a particle from the surface of earth (only particle in system) (s) Conversion of angular momentum about a specific point in the space CODES :   A B C D     a) B d c a     b) c,d b,a d a     c) d b a c     d) c d does not m d

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 (d) 1. For earth moving in an elliptical orbit, centripetal force passes through CM, so its torque will be zero at all points of motion. So angular, momentum can be conserved at all points of motion. But as external force is acting, linear momentum will be unconserved 2. Angular momentum can be conserved about the point of contact as work done about this point by force of friction is zero. Linear momentum will not be conserved as force of friction is an external force here 3. External forces acting on the system are normal reaction, and friction. Torque due to normal reaction and will be zero about the centre of mass but not of friction. So, angular momentum will not be conserved. Also in the presence of external forces, the linear momentum will not be conserved 4. For the projected particle, force of gravity which is external in this case will render linear momentum unconserved. But torque of this force will be zero as it will pass through the CM. So angular momentum is conserved instantaneously

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A block of mass is kept on a smooth horizontal surface and attached by a light thread to another block of mass . Block is resting on ground, and thread and pulley are massless and frictionless. A bullet of mass moving horizontally with velocity of penetrates through block and comes out with a velocity of 100 m/s Column-I Column- II (A) Velocity of the 2 kg block just after the bullet comes out (p) 50/3 (B) Maximum displacements of 1 kg block in left direction (q) 25 (C) Impulse by the string on block (r) 25/3 (D) Impulse by the particle on block (s) 5.2 CODES : A B C D a) c d a b b) a b d c c) b d a c d) b a c d 