Question

a trolley of mass 3 kg is connected to the two identical rubber bands in each of force constant 600 Newton per second one fidget roll is displayed from equilibrium position by 5 cm and released what is the period of ensuring oscillation

Answer 1

The mass of 3 kg goes up  and  mass of 4 kg comes down with an acceleration a.  The tension in the string is uniform through out its length and is T.

    T - 3 * g = 3 * a

    4 * g - T = 4 * a

  solving these,  a = g/7 = 1.4 m/sec/sec   and    T = 24 * 1.4 Newtons

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      Inelastic collision.  

  momentum is conserved after collision.  There is a loss of energy in collision.

    100 * 6 - 120 * 5 = (100+120) * v

          v = 0          =>    the combined mass becomes stationary.

Answer 2

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