Two bodies of masses m 1 = 5 kg and m 2 = 3 kg are connected by a light string going over a smooth light…

Two bodies of masses m1=5 kg and m2=3 kg are connected by a light string going over a smooth light pulley on a smooth inclined plane as shown in the figure. The system is at rest. The force exerted by the inclined plane on the body of mass m1 will be : [Take g=10 m s-2]

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  1. 30 N
  2. 40 N
  3. 50 N
  4. 60 N

Solution

The forces acting on two masses are shown below.

Here, N is normal to the incline and tension T along the string up the incline. As the string and the pulley are all light and smooth, the tension in the string is uniform everywhere.

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For equilibrium condition, forces should add to zero.

Thus, equating, m2g=m1gsinθ

sinθ=m2m1=35 and cosθ=45

Normal force on m1 is N=m1gcosθ=5gcosθ

=5×10×45=40 N

Asked in: JEE Main 2022 (29 Jul Shift 2)

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