a) 5 kN

b) 8 kN

c) 10 kN

d) 20 kN

the Answer is C)....can someone explain why?

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- Thread starter pizza1994
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a) 5 kN

b) 8 kN

c) 10 kN

d) 20 kN

the Answer is C)....can someone explain why?

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Gravity= (mass) (acceleration) = (1000kg)(10)

Height doesnt matter unless you are trying to find gravitational potentional potential energy

The distance between them could only work if maybe you wanted to know the work required to go from tower to tower,idk that factoid seemed pretty useless.

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Gravity= (mass) (acceleration) = (1000kg)(10)

Height doesnt matter unless you are trying to find gravitational potentional potential energy

The distance between them could only work if maybe you wanted to know the work required to go from tower to tower,idk that factoid seemed pretty useless.

I don't think this is right, because there would be more tension in the rope if the gondola were hanging 1 cm below the top of the towers than if it were hanging 200m below.

I haven't done this type of problem in a couple of years now, but I drew a free body diagram. The tension in the rope off to the upper left is X. The vertical component of the force is 1000 * 9.8 = 9.8 kN. The horizontal is therefore given in t sin(theta) = 9.8 kN, and theta is about 30 degrees. sin(30) is 0.5, so t ~ 20 kN, divided between left and right components. So that's 10 kN.

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Imagine the forces on the gondola. 9.8 kN straight down, then t1 to the upper left and t2 to the upper right. t1 and t2 both have a horizontal and vertical component. Since t1 = t2 (the angle is the same), the vertical component of each is 4.9 kN.

We determine the angle using tan theta = 100/170, so theta is about 30. sin(30) = 4.9 kN / t1. sin(30) is 0.5 so t1 = t2 = 9.8 kN.

The trick is to realize that though you have essentially two forces acting on the gondola: gravity, and the vertical component of the tension. However, the vertical component of the tension is really the sum of t1 and t2, each of which has a horizontal component that cancels out the other.

That is the part that confuses me.

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- Joined
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