Conservation of momentum problems

AI Thread Summary
The discussion focuses on a conservation of momentum problem involving a grand piano and a pianist. The piano has a mass of 1250 kg and moves forward at a velocity of 0.06 m/s after the pianist pushes off. The pianist rolls backward at a speed of 1.4 m/s. Using the conservation of momentum formula, the calculated mass of the pianist is 54 kg. The initial calculations and methodology are confirmed to be correct.
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The larges grand piano in the world is really grand. Built in London, it has a mass of 1250 kg. Suppose a pianist finishes playing this piano and pushes herself from the piano so that she rolls backwards with a speed of 1.4m/s. Meanwhile, the piano rolls forward so that in 4.0s it travels 24 cm at constant velocity. Assuming the stool that the pianist is istting on has a negligible mass, what is the pianist's mass?

a. v of piano= s/t= .24/4=.06m/s
b. mp2= -mpvp,f/vp2,f= (-1250*.06)/-1.4 = 54kg

Correct me if I'm wrong, thanks!
 
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