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Having trouble visualizing tension as it relates to cliffs or pulley systems with masses on both sides.
Specifically, EK Physics 1001 questions 241 and 244.
241) 50 kg woman holding a 50 kg mass from the end of a rope (pulley over the cliff to make it a straight drop). Question asks for the tension in the rope.
I assumed that the mass in in equilibrium so the forces up = forces down. Gravity is pulling down at 500N so the tension should also be 500N?
The answer is 250N but I can't really follow the explanation. How/Why does the mass of the woman matter?
244) Mass of m on the left side of a pulley, mass of 2m on the right side of the pulley. What is the tension in the rope in terms of mg?
No clue how to approach this one, I completely sucked at pulleys in physics and ended up just using shortcuts like mechanical advantage = # of ropes supporting pulley.
Basically, I don't know how to approach problems with masses on both sides of the pulley whether the mass be on a surface (first problem) or hanging in the air (second problem)?
Anyone want to explain the answers and/or point me towards a resource I can use to understand this type of problem??
Thanks!
Specifically, EK Physics 1001 questions 241 and 244.
241) 50 kg woman holding a 50 kg mass from the end of a rope (pulley over the cliff to make it a straight drop). Question asks for the tension in the rope.
I assumed that the mass in in equilibrium so the forces up = forces down. Gravity is pulling down at 500N so the tension should also be 500N?
The answer is 250N but I can't really follow the explanation. How/Why does the mass of the woman matter?
244) Mass of m on the left side of a pulley, mass of 2m on the right side of the pulley. What is the tension in the rope in terms of mg?
No clue how to approach this one, I completely sucked at pulleys in physics and ended up just using shortcuts like mechanical advantage = # of ropes supporting pulley.
Basically, I don't know how to approach problems with masses on both sides of the pulley whether the mass be on a surface (first problem) or hanging in the air (second problem)?
Anyone want to explain the answers and/or point me towards a resource I can use to understand this type of problem??
Thanks!