Need help with a problem

  • #1
A skier of mass 64 kg is pulled up a slope by a motor-driven cable. How much work is required to pull him 80 meters up a 30 degree slope (assumed frictionless) at a constant speed of 3.1 meters/second? [answer is to be in joules]


Ok, so the equation I am using is W = (Fcos(theta))*delta x

I tried using the values above and I've done it over and over and still came up with the same number.

W = ((3.1*64)*cos30)*80

= 13745.6

Am I missing something obvious? Thanks in advance for any helpful suggestions.
 

Answers and Replies

  • #2
Päällikkö
Homework Helper
519
11
If there was no slope, a force of what magnitude would be required to keep up a constant speed?
And as dW = F dx, how much work would be required for the 80m trip?

Hope this helps you figure out what you did wrong :).
 
Last edited:
  • #3
Ok, I got it . . .Thank you.
 

Related Threads on Need help with a problem

  • Last Post
Replies
1
Views
973
  • Last Post
Replies
2
Views
995
  • Last Post
Replies
5
Views
1K
Replies
1
Views
1K
  • Last Post
Replies
2
Views
1K
  • Last Post
Replies
1
Views
955
  • Last Post
Replies
1
Views
2K
  • Last Post
Replies
5
Views
1K
  • Last Post
Replies
1
Views
4K
  • Last Post
Replies
3
Views
840
Top