Don't Understand Tension in this Instance

  • Thread starter Lexielai
  • Start date
  • Tags
    Tension
In summary, the conversation discusses a homework problem involving a man hoisting himself into a tree using a nylon rope. The man exerts a downward force of 358 N on the rope, resulting in an upward acceleration. The sources used to solve the problem explain that the tension in the rope acts on both ends, causing the man to rise. However, the speaker is struggling to understand how the force on the hands transfers to the body. They request a visual aid to better understand the concept.
  • #1
Lexielai
3
0
Hello everyone!

I was doing a homework problem tonight, and a concept came up that I didn't quite understand. Don't worry, this is not a question asking for homework help -- I've already done the research and figured out how to solve for the solution. What I don't understand is why it's true.

For the sake of simplicity, I will be copying the homework problem here to clarify the circumstances.

To hoist himself into a tree, a 72.0 kg man ties one end of a nylon rope around his waist and throws the other end over a branch of the tree. He then pulls downward on the free end of the role with a force of 358 N. Neglect any friction between the rope and the branch, and determine the man's upward acceleration.

I've already researched a few other sources, so I know how the answer is derived, but I don't understand why it's true. In this instance, the man's exertion of 358 N creates a tension of 358. His weight, W = mg, is 705.6 N in this instance. Because tension acts on both ends of the rope, apparently, he rises because the tension is doubled, which would exceed 705.6 N and allow him to accelerate upwards.

According to the sources I've looked into, one end of the tension acts on his body, while the other acts on his hands. However, I have a hard time imagining a pulling force on his hands. When this action is done in real life, I don't feel as if my hands are being pulled upwards. Rather, my hands stay in the same location on the rope, and are possibly even lowered from their previous position while my body rises.

I suppose because the hands are a "part of the body" then the pulling force would transfer over to the body, but in that instance there would still be a pulling force on the hands. How does this force manifest? A picture/diagram would probably be very helpful in explaining this! ;)

Thanks in advance!
 
Physics news on Phys.org
  • #2
Lexielai said:
When this action is done in real life, I don't feel as if my hands are being pulled upwards. Rather, my hands stay in the same location on the rope, and are possibly even lowered from their previous position while my body rises.
If you are pulling down on the rope, the rope must be pulling you up. Just because your hands lower, doesn't mean that an upward force isn't being exerted on your body. (The force is transmitted through your hand and arm to your torso.)
 

1. What is tension in science?

Tension in science refers to the force that is applied to an object when it is being pulled or stretched. It is a type of mechanical stress that can cause changes in shape or movement of an object.

2. How is tension measured?

Tension is typically measured in units of force, such as newtons (N) or pounds (lbs). It can be measured using various instruments, such as a tension balance or a spring scale.

3. What are some examples of tension in everyday life?

Examples of tension in everyday life include the tension in a rubber band when it is stretched, the tension in a rope when it is being pulled, and the tension in a bridge's cables that hold up its weight.

4. How does tension affect materials?

Tension can cause materials to deform or break if it exceeds their maximum tensile strength. It can also affect the elasticity and flexibility of materials, as well as their ability to withstand external forces.

5. What is the importance of understanding tension in science?

Understanding tension is important in various fields of science, such as engineering, physics, and biology. It allows us to predict and control the behavior of materials under different forces, and design structures that can withstand tension without breaking or deforming.

Similar threads

Replies
2
Views
1K
Replies
4
Views
1K
Replies
5
Views
943
Replies
40
Views
3K
Replies
12
Views
1K
Replies
14
Views
3K
  • Introductory Physics Homework Help
2
Replies
38
Views
1K
Replies
12
Views
1K
Replies
9
Views
3K
Back
Top