The centre of mass of a body is a point at which the entire mass of the body is supposed to be concentrated. The position vector `overset rarr(r )` of c.m of the system of tow particles of masses `m_(1)` and `m_(2)` with position vectors `overset rarr(r_(1))` and `overset rarr(r_(2))` is given by `overset rarr(r ) = (m_(1)overset rarr(r_(1)) + m_(2)overset rarr(r_(2)))/(m_(1) + m_(2))` For an isolated system, where no external force is acting, `overset rarr(v_(cm)) =` constant Under no circumstances, the velocity of centre of mass of an isolated system can undergo a change With the help of the comprehension given above, choose the most appropriate alternative for each of the following questions : A bomb dropped from an aeroplane in level flight explodes in the middle. the centre of mass of the fragmentsA. is a restB. moves vertically downwardsC. moves vertically upwardsD. continues to follow the same parabolic path which it would have followed if there was no exposion.

The centre of mass of a body is a point at which the entire mass of th

1.	The centre of mass of a body is a point at which the entire mass of the body is supposed to be concentrated. The position vector `overset rarr(r )` of c.m of the system of tow particles of masses `m_(1)` and `m_(2)` with position vectors `overset rarr(r_(1))` and `overset rarr(r_(2))` is given by `overset rarr(r ) = (m_(1)overset rarr(r_(1)) + m_(2)overset rarr(r_(2)))/(m_(1) + m_(2))` For an isolated system, where no external force is acting, `overset rarr(v_(cm)) =` constant Under no circumstances, the velocity of centre of mass of an isolated system can undergo a change With the help of the comprehension given above, choose the most appropriate alternative for each of the following questions : A bomb dropped from an aeroplane in level flight explodes in the middle. the centre of mass of the fragmentsA. is a restB. moves vertically downwardsC. moves vertically upwardsD. continues to follow the same parabolic path which it would have followed if there was no exposion.
Answer» Correct Answer - D As explosion is due to inertal forces only, the centre of mass of fragments continues to follow the same parabolic path, which it would have followed, if there was no explosion.

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