Q 1 :

In a system, two particles of masses m1=3 kg and m2=2 kg are placed at a certain distance from each other. The particle of mass m1is moved towards the center of mass of the system through a distance of 2 cm. In order to keep the center of mass of the system at the original position, the particle of mass m2 should move towards the center of mass by the distance ___ cm.               [2024]



(3)

ΔXC.O.M=m1Δx1+m2Δx2m1+m2

0=3×2+2(-x)3+2⇒x=3 cm

 



Q 2 :

Two identical bodies A and B of equal masses have initial velocities v→1=4i^ m/s and v→2=4j^ m/s respectively. The body A has acceleration a→1=6i^+6j^ m/s2 while the acceleration of the other body B is zero. The centre of mass of the two bodies moves in ______ path.                [2026]

  • circular

     

  • parabolic

     

  • straight line

     

  • elliptical

     

(3)

v→cm=m1v→1+m2v→2m1+m2=m(4i^)+m(4j^)2m=(2i^+2j^) m/s

a→cm=m1a→1+m2a→2m1+m2=m(6i^+6j^)+m(0)2m=3i^+3j^

v→cm and a→cm are along same line so path is a straight line.