Physics 9702 · AS & A Level · Momentum and Newton's laws of motion

Momentum and Newton's laws of motion — practice question

A submarine with a total mass of $3200\,\text{kg}$ is stationary beneath the water. Its total mass is then reduced by $200\,\text{kg}$, as water is pumped out horizontally from the submarine in a negligible time. The upthrust on the submarine remains the same. Because the total weight of the submarine changes, it accelerates vertically upwards. What is the submarine's initial upwards acceleration?

  • A$0.613\,\text{m s}^{-2}$
  • B$0.654\,\text{m s}^{-2}$
  • C$9.81\,\text{m s}^{-2}$
  • D$10.5\,\text{m s}^{-2}$

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