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I need some help in this problem to see if my game plan is right. My answer doesn't make sense, well to me it doesn't.
A weight of 200 lb hangs from a frame of negligible weight, as shown. If the frame is in equilibrium, determine the loads acting on the frame at A and D. Use the fact that the frame acts as a threefoce element to check your answer.
they are all pin connections
theres a 45 45 90 degree triangle there.
First off i drew a FBD for just DB, and found that it is a two force element, so the line of action passes through the force points of application.
Then when i draw a FBD for ABC the forces at B, it is just a force pointing at a 45 degree angle. Then theres a force Ay and Ax at A and the 200 lb force acting downward at C.
the sum of the forces in the x direction
Ax B cos45 = 0
The sum of the force in the y direction
Ay + B sin45  200 lb = 0
The sum of the moments in the z direction at point A
(6ft)(200lb) + (3ft)(Bsin45) = 0
A weight of 200 lb hangs from a frame of negligible weight, as shown. If the frame is in equilibrium, determine the loads acting on the frame at A and D. Use the fact that the frame acts as a threefoce element to check your answer.
they are all pin connections
theres a 45 45 90 degree triangle there.
First off i drew a FBD for just DB, and found that it is a two force element, so the line of action passes through the force points of application.
Then when i draw a FBD for ABC the forces at B, it is just a force pointing at a 45 degree angle. Then theres a force Ay and Ax at A and the 200 lb force acting downward at C.
the sum of the forces in the x direction
Ax B cos45 = 0
The sum of the force in the y direction
Ay + B sin45  200 lb = 0
The sum of the moments in the z direction at point A
(6ft)(200lb) + (3ft)(Bsin45) = 0
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