Tension on the table top pulley

[ptrainerjoe]

heres the problem:

A person pulls a heavy load of mass 37kg up the side of a building by using a frictionless pulley. The load travels up a distance of 7.5m. Take the load to move with ocnstant velocity and ignore any acceleration at the beginning or end of the move. How much work is done by the tension in the rope?

I know the work done by the person and gravity(which are the other two parts of the question) but I'm getting stuck on this part. I'm thinking it would be zero but the rope is moving so i don't know

Thanks for the help.

 

[HallsofIvy]

Work equals force times distance. That's all you need.

Since there was no accleration, the force in the rope is exactly equal to the weight of the load.

 

[wais]

The tension on the table top pulley is an important factor to consider in this problem. In order for the load to move with a constant velocity, the tension in the rope must be equal to the weight of the load. This is because the upward force of the tension must balance out the downward force of gravity acting on the load.

In this scenario, the tension in the rope would be equal to the weight of the load, which is 37kg multiplied by the acceleration due to gravity (9.8m/s^2), giving us a tension of 362.6N. This tension remains constant throughout the 7.5m distance that the load is pulled.

Now, to calculate the work done by the tension in the rope, we can use the formula W = Fd, where W is work, F is force, and d is distance. In this case, the work done by the tension would be 362.6N multiplied by 7.5m, giving us a total work of 2719.5J.

It is important to note that while the rope is moving, the tension is not actually doing any work on the load. The work is being done by the person pulling the rope, using their own energy and exerting a force on the rope. The tension in the rope is simply a means of transferring this force to the load.

In conclusion, the work done by the tension in the rope in this scenario is 2719.5J. I hope this helps clarify any confusion you may have had. Keep up the good work!