A boat of mass m is carrying a load of bricks with a total number of N and mass M, and is floating freely on water. SUPERMAN, in a show of strength, throws the entire load of bricks backward at once with a relative speed of v0. A GENIUS, in a show of intelligence, throws the bricks backward with a relative speed of v0 one at a time. Argue and explain how and why GENIUS achieves a much higher speed than SUPERMAN. Take N >> 1 and M >> m. Neglect the friction between the boat and water, and the mass of GENIUS and SUPERMAN.(adsbygoogle = window.adsbygoogle || []).push({});

I think i know how to get the velocity of the boat in the case where SUPERMAN throws the bricks all at once.

But the problem comes when the bricks are thrown one by one. In this case, the velocity of the brick,relative to the eart, is decreasing everytime the brick is thrown. Should i use the velocity of the brick relative to the earth, or relative to the boat to do this question?

Also the mass constantly decreases... for every throw, velocity and mass changes...

i have no clue on how to show that GENIUS achieves higher speed than SUPERMAN.

I need some help.... somebody.. please help me~~!!

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# Homework Help: Conservation of Momentum.Boat Question

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