- #1
brake4country
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Homework Statement
A 100 kg man dangles a 50 kg mass from the end of a rope. If he stands on a frictionless surface and hangs the mass over a cliff with a pulley, the tension in the rope will be:
(A) 250 N
(B) 333 N
(C) 500 N
(D) 667 N
The answer is B but I am having a difficult time setting this one up.
Homework Equations
F=ma
The Attempt at a Solution
Okay, so we know that for the man, T = ma because he is on a frictionless surface and the block is mg = T+ma.
Some others have posted this problem on this site but I need clarification for the second equation listed above. I cannot combine these equations because the masses are different. So, what I did was alter the equations as
man: T=2ma
block: mg = T+ma
substituting gives me: mg = 2ma +ma
therefore, g = 3a and a = 3.33 m/s
But when I go back to my "altered" equations to solve for T, I get 667 N which is wrong. Anyone know what I am doing wrong here?