Help with a couple physics problems

  • #1
masteroftheuniverse
1
0
I am having some trouble with a couple of physics h/w problems and would appreciate any help you can give me..

Julie pulls a 61.5 N bag a distance of 278 m at a constant velocity. The force she exerts is 48.4 N at an angle of 66.8 degrees above the horizontal.
I found the work julie does on the bag to be 5300 J.
Yet I am not sure how to find A) the work done by the force of friction on the bag and B) the coefficient of kinetic friction on the bag

Next problem is
A rain cloud contains 2.82 x 10^7 kg of water vapor.
The acceleration of gravity is 9.81m/s^2
How long would it take a 2.10 kW pump to raise the same amount of water to the cloud's altitude of 1.44km? Answer in seconds (s)
[I tried Power= work(FsCOS[theta]) divided by t. So 2100w=2.82x10^7(9.81)1440m COS 90 degrees DIVIDED by t, which just equals 0 since cos90 is 0. I DONT GET IT!]
 
Physics news on Phys.org
  • #2
why is theta 90? why is this not in the Homework forum?
 

Similar threads

Replies
2
Views
9K
Replies
1
Views
4K
Replies
2
Views
3K
Replies
1
Views
3K
Replies
2
Views
2K
Replies
2
Views
3K
Back
Top