a piano is rolling down on a frictionless slope at an ever increasing speed.the piano tuner sees it,runs up to it and pushes on it,slowing it down to a constant speed.the magnitude of the force on the man by the piano is fmp the magnitude of the force on piano by the man is fpm if we compare these forces what will we find?

 when the piano is moving at a constant speed_MP = F_PM while the piano slows down but F_MP > F_PM)Therefore, F_MP) is equal to the force due to piano on the piano tuner (F_PM). But when the piano is moving at a constant speed, the acceleration of the piano is zero and the net force on the piano will be zero. So, when the piano is moving at a constant speed, applied force by the piano tuner on piano (F_MP) is greater than the force due to piano on the piano tuner (F_PM when the piano is moving at constant speed.The piano starts to decelerate when it is slowing down. At this time, the applied force by the piano tuner on piano (F_MP = F_PM while the piano slows down but F_MP > F_PMF

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