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fp252
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Hello, I've been unable to figure this question about tension and torque out.
1. The question is: calculate the torque about the front support on the right of a diving board exerted by a 70 kg person 3.0 m from that support.
This is a crude diagram of a person on a diving board, where
D = a diver, and || means a diving board support:
____________________________________________D
||<----1.0m---->||<-----------3.0m-------------->
||- - - - - - - - - ||
||- - - - - - - - - ||
2. Relevant equations:
τ = Fd
F = ma
Fup = Fdown / Fleft = Fright
3. I get these equations:
Fup = Fdown
F1 + F2 = Mg + mg (where mg = downward force of diver, Mg = downward force of diving board at center of board)
F1 + F2 = M(9.8) + 686
τcw = τccw
Mg(1.5) + mg(3) = F2(1) (assuming F2 is the upward force for the middle support?)
Mg(1.5) + 70(9.8)(3) = F2(1)
Mg(1.5) + 2058 = F2
I assume the pivot point to be on the far left of the board. The main problem problem with both of these are that I end up with equations that have two variables. Also, I don't have M, which is the mass of the diving board - how would I figure this out?
What's wrong in my process to get the answer?
1. The question is: calculate the torque about the front support on the right of a diving board exerted by a 70 kg person 3.0 m from that support.
This is a crude diagram of a person on a diving board, where
D = a diver, and || means a diving board support:
____________________________________________D
||<----1.0m---->||<-----------3.0m-------------->
||- - - - - - - - - ||
||- - - - - - - - - ||
2. Relevant equations:
τ = Fd
F = ma
Fup = Fdown / Fleft = Fright
3. I get these equations:
Fup = Fdown
F1 + F2 = Mg + mg (where mg = downward force of diver, Mg = downward force of diving board at center of board)
F1 + F2 = M(9.8) + 686
τcw = τccw
Mg(1.5) + mg(3) = F2(1) (assuming F2 is the upward force for the middle support?)
Mg(1.5) + 70(9.8)(3) = F2(1)
Mg(1.5) + 2058 = F2
I assume the pivot point to be on the far left of the board. The main problem problem with both of these are that I end up with equations that have two variables. Also, I don't have M, which is the mass of the diving board - how would I figure this out?
What's wrong in my process to get the answer?