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A 2000 k g rocket in free space expels 0.5 k g of gas per second at exhaust velocity 400 m s - 1 for 5 s . The increase in the speed of the rocket in this time is

Options

  1. A2000 m s - 1
  2. B200 m s - 1
  3. C0.5 m s - 1
  4. Dzero

Correct answer

C. 0.5 m s - 1

Step-by-step solution

d m d t × u = M d v d t 0.5   ×   400 = 2000   × ∆ v 5 ⇒ ∆ v = 0.5   m  s - 1

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