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NEST2020PhysicsLaws of Motion

A spherical raindrop of initial mass M₀ and initial radius R falls freely from rest. Let be the constant density and r the radius at time t . Assume that the drop maintains it's spherical shape. The drop loses mass at the rate d m / d t=-4 k r^2 . where k is a constant. Define t_c= R k . Select the correct statement(s)

Options

  1. AThe speed of the drop at time t_c / 2 is 15 g R / 8 k
  2. BThe rate of mass loss goes to zero as time t t_c
  3. CThe drop loses all it's mass in time t_c
  4. DThe momentum approaches M₀ g R / 4 k as t t_c

Correct answer

D. The momentum approaches M₀ g R / 4 k as t t_c

Step-by-step solution

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