# Centre of mass of a system is unique point which is very helpful in solving the problems related to the motions of rigid bodies. In columns I and II, some statements regarding centre of mass are given. Match the columns: Column-I Column- II (A) In the absence of external forces, the internal forces (p) Inside the material of the body (B) Centre of mass of a body can be (q) May affect the motion of individuals (C) The kinetic energy of the system of two blocks (r) Do not affect the motion of centre of mass (D) Centre of mass of a solid cylinder is (s) Outside the material  of the body CODES :   A B C D     a) B,c a,d c a     b) a,d c b,c a     c) b,c a a,d c     d) c b,c a,d a

## Question ID - 101091 :- Centre of mass of a system is unique point which is very helpful in solving the problems related to the motions of rigid bodies. In columns I and II, some statements regarding centre of mass are given. Match the columns: Column-I Column- II (A) In the absence of external forces, the internal forces (p) Inside the material of the body (B) Centre of mass of a body can be (q) May affect the motion of individuals (C) The kinetic energy of the system of two blocks (r) Do not affect the motion of centre of mass (D) Centre of mass of a solid cylinder is (s) Outside the material  of the body CODES :   A B C D     a) B,c a,d c a     b) a,d c b,c a     c) b,c a a,d c     d) c b,c a,d a

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(a)

i.Internal forces may affect the motion of individual particles of a system, but not that of the centre of mass

ii. Centre of momentum of a body can be inside or outside the body

iii. Kinetic energy of a system of two blocks may increase, decrease or remain same with time, but it will have no effect on motion of the centre of mass

iv. centre of mass of a solid cylinder is inside the cylinder

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