It is desired that the 100-lb container, when released from rest in the position

Question

It is desired that the 100-lb container, when released from rest in the position shown, have no velocity after dropping 7 ft to the platform below. Specify the proper weight W of the counterbalancing cylinder. My attempt: U_1,2 + T_1 +V_1 = T_2 + V_2 T_1 = V_1 = T_2 = 0 ~ both velocities zero, and datum makes PE zero Using a FBD, T = W. On the bucket, mg = 100 lb = 2T (5/13) V_2 = mgh = (100)(7) = 700 U_1,2 = force*distance THEREFORE, [2T*(5/13)]*5' = 700 W = T = 182 lb The answer is W = 88.1 lb

Explanation / Answer

wow that formatted odd. you have to set up a a triangle for the starting position of sides 12/5/?, solve using pythagorian therom. ?=13 set a triangle for the final position, 5+7=12 so you get a 12/12/? triangle. solve using pythagorian therom ?=16.97 d=2x(16.97-13) d=7.94. You have your tension wrong, if there is 2 forces acting up and one acting down. the up forces are only half T U_1,2= f*d = T*d =mgh T=700/7.94 T=88.1 lb I hope thats right...

Related Questions

Navigate

• Browse (All)
• Browse I
• Subjects

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.