Calculating Work done by a force

Join the discussion
Registration is free. Ask a follow-up in this thread, or start your own.
1 reply · 1K views
Eikcuhc
Messages
1
Reaction score
0

Homework Statement


[URL]http://einstein.math.fsu.edu:9080/testbanks/wiley/math/1114ptF08/cch/images/qu.215.9.question.gif[/URL]

Homework Equations


I know that
W = Fd where here it is
W = F * [tex]{\rightarrow}{\}[/tex]AB

Also, that

(im sorry, this looks really ugly)
[tex]\stackrel{v\rightarrow}{}[/tex] = ||v||(cos[tex]\alpha[/tex][tex]\stackrel{i\rightarrow}{}[/tex]+sin[tex]\alpha[/tex][tex]\stackrel{j\rightarrow}{}[/tex])
||v|| = sqrt(a2+b2)


The Attempt at a Solution


I get stuck fairly quickly on this problem, my professor never went on it in class.

using the second equation, I get to the point of

v = (sqrt13)(cos+sin)

I am not sure what goes into the cos and sin portion of the problem, I am assuming it has something to do with the coordinates it gives, but other than that, I have no idea.
 
Last edited by a moderator:
Physics news on Phys.org
Ok, so your force is 5lbs in the direction of 3i+2j, so what is your force vector F?

The displacement is from (0,0) to (0,4), what is you displacement vector d equal to?