How much work is done when carrying a load up a set of stairs?

  • Thread starter Thread starter Blonde1551
  • Start date Start date
  • Tags Tags
    Work
AI Thread Summary
The discussion centers on calculating the work done by a man carrying a 70.0 kg box while navigating different distances, including up a set of stairs. Participants express confusion regarding the lack of information about the direction of movement and whether he is walking at a constant velocity. The consensus leans towards calculating work only when ascending the stairs, using the formula W=fd, specifically considering the vertical distance. There is debate about the interpretation of the distance mentioned in the problem, with suggestions that it should refer to the vertical height rather than the slope distance. Ultimately, clarification is sought on how to accurately determine the work done on the box in this scenario.
Blonde1551
Messages
5
Reaction score
0

Homework Statement



A man carries a 70.0 kg box. He caries it down a hallway 10.0 m, up a set of stairs for 4.0 meters, and down another hallway for 15.0 meters. How much work does he do?

Homework Equations



W=fd

The Attempt at a Solution



I am confused because I don't feel like there is enough information to answer. The problem doesn't say if he is walking at a constant velocity or not, but I assume he is. And it doesn't say what direction he is walking in. I feel like this is a trick question and no work is being done, but I am not sure because he walks up a set of steps.

I would guess that the work being done is only when he is walking up the steps?
And the answer would be (70.0)(9.81)(4.0). Would this be correct?

Can someone please explain this to me?
Thanks!
 
Last edited:
Physics news on Phys.org
Maybe the question is 'how much work is done on the box' in which case I agree with your answer.
 
The main thing I don't like about the question is that "up a set of stairs for 4.0 meters" would normally mean the distance walked (up the line of slope). Being in the context of distances along horizontals reinforces that. But to answer the question, without being told the angle of the flight of steps, you need to assume it's the vertical distance.
 
Kindly see the attached pdf. My attempt to solve it, is in it. I'm wondering if my solution is right. My idea is this: At any point of time, the ball may be assumed to be at an incline which is at an angle of θ(kindly see both the pics in the pdf file). The value of θ will continuously change and so will the value of friction. I'm not able to figure out, why my solution is wrong, if it is wrong .
TL;DR Summary: I came across this question from a Sri Lankan A-level textbook. Question - An ice cube with a length of 10 cm is immersed in water at 0 °C. An observer observes the ice cube from the water, and it seems to be 7.75 cm long. If the refractive index of water is 4/3, find the height of the ice cube immersed in the water. I could not understand how the apparent height of the ice cube in the water depends on the height of the ice cube immersed in the water. Does anyone have an...
Thread 'A bead-mass oscillatory system problem'
I can't figure out how to find the velocity of the particle at 37 degrees. Basically the bead moves with velocity towards right let's call it v1. The particle moves with some velocity v2. In frame of the bead, the particle is performing circular motion. So v of particle wrt bead would be perpendicular to the string. But how would I find the velocity of particle in ground frame? I tried using vectors to figure it out and the angle is coming out to be extremely long. One equation is by work...
Back
Top