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So how do you find tension ?You have two equations, one for the man and one for the dumbwaiter, and two unknowns, the acceleration and the tension.
So how do you find tension ?You have two equations, one for the man and one for the dumbwaiter, and two unknowns, the acceleration and the tension.
The normal force between the man and the dumb waiter (we can ignore the scale since that is considered massless, so just transmits the force straight through) must be up on one and down on the other. Does it act down on the man and up on the dumb waiter or the other way around?It’s going up , so shouldn’t it be added to tension
Wouldn’t it be the other way around ? Up on the man and down on the dumbwaiter ?The normal force between the man and the dumb waiter (we can ignore the scale since that is considered massless, so just transmits the force straight through) must be up on one and down on the other. Does it act down on the man and up on the dumb waiter or the other way around?
My teacher explained to use two different equations when two variables are unknown, I was trying to find another equation to substitute T withUp on the man and down on the elevator is correct. Your equation in post #22 is also correct. Where does your equation in post #24 come from?
You have the correct information for the man in post #5.My teacher explained to use two different equations when two variables are unknown, I was trying to find another equation to substitute T with
Use 209 newtons for F_{n} and mg for F_{g}, of course with 82 kg for the man's mass.Fn=209N (the scale reading)
Fg=mg
=(82kg)(9.8) = 803.6 N
And the force exerted on the rope is T
So the formula would be,
(Fn +T)-Fg=ma
Am I wrong or missing something ?
Use those two equations to eliminate T (or eliminate a if you'd rather find the tension).Oh, I see
So then it’ll be
T-209N-40g=40a ?
Right, but in post #16 you had an equation for the dumb waiter with T....+Fn = ...Wouldn’t it be the other way around ? Up on the man and down on the dumbwaiter ?