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JEE Main20205 Sep 2020Evening ShiftPhysicsLaws of MotionActual

A spaceship in space sweeps stationary interplanetary dust. As a result, its mass increases at a rate d M ( t ) d t = b v 2 ( t ) , where v ( t ) is its instantaneous velocity. The instantaneous acceleration of the satellite is:

Options

  1. A- b v 3 ( t )
  2. B- b v 3 M ( t )
  3. C- 2 b v 3 M ( t )
  4. D- b v 3 2 M ( t )

Correct answer

B. - b v 3 M ( t )

Step-by-step solution

dM ( t ) dt = - bv 2 in free space no external force so there in only thrust force on rocket f i n   = d M d t V r e l M a = - b v 2 ( t ) v a = - bv 3 M ( t )

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