How Is Tension Calculated in a Rope Held by Two People Leaning Back?

AI Thread Summary
The discussion revolves around calculating the tension in a rope held by two people leaning back at a 15-degree angle. The initial approach involved using a force diagram and the relationship between gravitational force and tension, but there was confusion regarding the x-component of gravity. Participants clarified that gravity acts only in the vertical direction and does not have an x-component. The suggestion was made to consider torque in the analysis for a more accurate solution. Overall, the conversation emphasizes the need for a correct understanding of forces and their components in this scenario.
haloschief
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1. Two people of equal mass are holding opposite ends of a rope and lean back 15 degrees with the vertical. What is the tension in the rope exerted by each person?

This is how attempted to solve this.
So tension is created by the force of gravity from them leaning back. So I drew a force diagram sum of the tensions in the X direction should be 0. So I found the force gravity in the X direction using Tan15=T/MG which gives me MGtan15=T.

Is this the correct way to set up the problem?

Thanks
 
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Looks good to me.
 
Ok, so I looked at this problem again and I'm still unsure about this solution. If gravity acts only on the y direction how is it possible for it to have an x-component and solve it like I just did? Should I be taking torques into account as well as the force exerted by the ground?
 
haloschief said:
Ok, so I looked at this problem again and I'm still unsure about this solution. If gravity acts only on the y direction how is it possible for it to have an x-component and solve it like I just did?
It doesn't. Assuming your y-axis is vertical, gravity doesn't have any x-component. I'm not really sold on your original solution either. (Kudos for recognizing that there was something fishy about it :wink:)

I think trying to do it with torque would be a good idea.
 
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