Question

A bear sling is used in some national parks for placing backpackers' food out of the reach of bears. Explain why the force needed to pull the backpack up increases as the backpack gets higher and higher. Is it possible to pull the rope hard enough so that it doesn't sag at all?

Answer 1

Answer:

Explanation:

The force needed to pull up the backpack up increases as the backpack gets higher because the force of gravity needs to be encountered by the tension of the string. According to the formula to calculate the tension, assuming both are equal $T=\frac{Fg}{(2Sin\theta)}$, the force of tension increases as the angle(with respect to horizontal axis) decreases. It is not possible to pull the rope hard enough because there will be no force in the y direction to counter the Fg; therefore, infinite force is needed.