Physics-
General
Easy
Question
Two masses 2 m and 
are connected by an inextensible light string. The string is passing over a light frictionless pulley. The mass 2 m is resting on a surface and mass m is hanging in air as shown in Fig. A particle of mass m strikes the mass from below in case (1) with a velocity 
and in case (II) strikes the mass m with a velocity from top and sticks to it.
- The conservations of linear momentum can be applied in both the cases just before and just after collision.
- The conservation of linear momentum can be applied in case I but cannot be applied in case II just before and just after collision.
- The ratio of velocities of mass just after collision in frist and second cases is 1/2
- The ratio of velocities of mass just after collision in first and second case is 3 .
just after collision in frist and second cases is 1/2
just after collision in first and second case is 3 .
The correct answer is: The conservation of linear momentum can be applied in case I but cannot be applied in case II just before and just after collision.
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