What Happens to the Bananas When a Monkey Climbs the Rope?

[joe215]

A 20 kg monkey holds on to a rope that passes over a frictionless pulley and is attached to a 20 kg bunch of bananas. The monkey starts to climb the rope to get the bananas.
a. as the money climbs, do the bananas move up, down, or remain at rest?
b. as the money climbs does the distance between the money and bananas increase, decrease, or remain the same?
c. the monkey let's go of the rope. before reaching the ground he grabs the rope to stop his fall. what do the bananas do?

a:remain at rest
b:remain the same
c:the bananas fall. then rise, then descend to the same level as the monkey

I think those are the answers, but I'm not sure why. thanks for any help!

 

[Rake-MC]

(a) think of it this way, initially the system is in equilibrium so there is the force of mg in the negative y direction on either side of the pulley.
When the monkey starts to climb he accelerates . Think of the connection between acceleration and force.

(b) This depends almost directly to your answer of question (a). Ie. if as he climbs the bananas move up at the same rate, then the distance remains the same.
explain your reasoning for this question please

(c) Why do the bananas rise? Remember the monkey and the bananas have the same mass, when they fall they fall at the same rate.

 

[baba89]

As the monkey climbs, the bananas will remain at rest because the pulley system allows for equal and opposite forces to be applied to both ends of the rope. This means that the force pulling the bananas down will be balanced by the force pulling the monkey up, keeping the bananas in place.

The distance between the monkey and the bananas will also remain the same, as the rope is fixed to the pulley and the monkey is pulling on it with a constant force. This means that the length of the rope between the monkey and the bananas will not change.

When the monkey lets go of the rope, the bananas will initially fall due to gravity. However, as the monkey grabs the rope again, the bananas will also start to rise with the monkey. This is because the force applied by the monkey on the rope will also be applied to the bananas, causing them to move up with the monkey. Once the monkey stops falling and is suspended by the rope, the bananas will descend to the same level as the monkey due to the equal and opposite forces acting on both ends of the rope.