A man with mass 70.0 kg stands on a platform with mass 25.0 kg. He pulls on the free end of a rope that runs over a pulley on the ceiling and has its other end fastened to the platform. The mass of the rope and the mass of the pulley can be neglected, and the pulley is frictionless. The rope is vertical on either side of the pulley.(adsbygoogle = window.adsbygoogle || []).push({});

With what force does he have to pull so that he and the platform have an upward acceleration of 1.80m/s^2

ok so my force diagram shows 2 forces acting on this firstly there is the force of mg pointing down. then there is the force of acceleration in the upward direction and this is equal to a*g.

so the way i figured the problem is that mg+ag=T wher T is the tension in the rope. the reason that i got this equation is because the force needed to pull the platform and person up must be the acceleration upward plus the gravity times the mass. However i dont think this reasoning is right so any help on this would be helpful. thanks

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# Homework Help: Forces and acceleration of pulled rope

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