JEE Main · 2024 · 04 Apr 2024 · Shift 2 · Conservation of Momentum

In a system two particles of masses

m_{1} = 3 kg

and

m_{2} = 2 kg

are placed at certain distance from each other. The particle of mass

m_{1}

is moved towards the center of mass of the system through a distance 2 cm . In order to keep the center of mass of the system at the original position, the particle of mass

m_{2}

should move towards the center of mass by the distance ________ cm .

Answer: 3

Solution

For the centre of mass to stay fixed, the moments of the two displacements about the COM must balance:

m_{1} d_{1} = m_{2} d_{2} ⟹ (3) (2) = (2) d_{2} ⟹ d_{2} = 3 cm

JEE Main · 2024 · 04 Apr 2024 · Shift 2 · Integer answer

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