What Is the Work Done in Climbing and Descending a Hill?

AI Thread Summary
The discussion focuses on calculating the work done by a man climbing and descending a hill at a 30-degree angle with a mass of 50 kg and uniform acceleration of 2 m/s². Participants suggest using the formula for work done, which is Work = Force * Displacement, and emphasize the importance of considering the angle of the hill in the calculations. The conversation also touches on the work-energy theorem as an alternative approach to determine the work done. Participants inquire about additional information, such as the height of the hill and the distance moved, which are crucial for accurate calculations. Overall, the thread explores various methods to solve the problem of work done in climbing and descending a hill.
darwined
Messages
18
Reaction score
0
Suppose a man is climbing up a hill at angle 30 degree from the ground. The mass of the man is 50Kg and he climbs up the hill at uniform acceleration of 2m/s2.

What is the work done in climbing up the hill and if he climbs down the hill at the same 30 degree angle with uniform acceleration of 2m/s2, what is the work done in climbing down the hill.

Thank you.
 
Physics news on Phys.org
That's an interesting question - how have you been attempting it so far?
How are you thinking about it?

Were you supplied with any other information - like the time spent climbing or the height of the hill?
 
  • Like
Likes 1 person
I have been thinking it in terms of Work done=Force * Displacement.

I guess we should use scalar product of vectors.Distance is along the ground and force is along the line which is 30degrees from the ground.
 

Attachments

  • Cimbing up and down.JPG
    Cimbing up and down.JPG
    4.8 KB · Views: 618
Sure, you can get the net force from F=ma.
What's the total applied force doing the work though?

Do you know how to find the distance moved?

OTOH: you can use the work-energy theorem.
 
Sure, you can get the net force from F=ma.
What's the total applied force doing the work though?

Do you know how to find the distance moved?

OTOH: you can use the work-energy theorem.
 
I multiplied the values first without the error limit. Got 19.38. rounded it off to 2 significant figures since the given data has 2 significant figures. So = 19. For error I used the above formula. It comes out about 1.48. Now my question is. Should I write the answer as 19±1.5 (rounding 1.48 to 2 significant figures) OR should I write it as 19±1. So in short, should the error have same number of significant figures as the mean value or should it have the same number of decimal places as...
Thread 'A cylinder connected to a hanging mass'
Let's declare that for the cylinder, mass = M = 10 kg Radius = R = 4 m For the wall and the floor, Friction coeff = ##\mu## = 0.5 For the hanging mass, mass = m = 11 kg First, we divide the force according to their respective plane (x and y thing, correct me if I'm wrong) and according to which, cylinder or the hanging mass, they're working on. Force on the hanging mass $$mg - T = ma$$ Force(Cylinder) on y $$N_f + f_w - Mg = 0$$ Force(Cylinder) on x $$T + f_f - N_w = Ma$$ There's also...
Back
Top