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## Homework Statement

A man pulls himself up, the acceleration is 1 m/s², the man's mass is 60 kg and the elevator's mass is 40 kg.

a) Calculate the tension in the rope.

b) Calculate the force that the man exerts on elevator's floor.

## Homework Equations

Fr = Ma

## The Attempt at a Solution

I calculated letter a) correctly, and found 550N. My problem is on letter b).

Here are my thoughts: The man's free body diagram on the elevator would be: His weigh down, and the elevator's normal (opposing to the force he exerts by newton's 3rd law) up, the difference of those would accelerate him, so, in symbols:

[itex]

N_{elevator} - P_{man} = m_{man}a\\\\

a = 1\frac{m}{s^2}; P_{man} = 588 N;\\

N_{elevator} = 588 + 60 = 648N

[/itex]

However, the answer is supposed to be 110 N. I also noticed that 648N - 550 N is almost equal to 110N, however that doesn't make much sense, since there are two tensions acting on him, and not only one.

Thanks in advance.