Name: Anonymous 2009-10-08 0:33
This was on a GRE practice test:
Let F be a constant unit force that is parallel to the vector (-1,0,1) in xyz-space. What is the work done by F on a particle that moves along the path given by (t,t^2,t^3) between time t=0 and time t=1?
What I want to say is (integrals are from 0 to 1) :
W = ʃF ds
= ʃ(-1/√2,0,1/√2)•(1,2t,3t^2)dt
= ʃ(-t/√2+3t^2/√2)dt
= 0
That's the right number, but is that the way to do it?
Let F be a constant unit force that is parallel to the vector (-1,0,1) in xyz-space. What is the work done by F on a particle that moves along the path given by (t,t^2,t^3) between time t=0 and time t=1?
What I want to say is (integrals are from 0 to 1) :
W = ʃF ds
= ʃ(-1/√2,0,1/√2)•(1,2t,3t^2)dt
= ʃ(-t/√2+3t^2/√2)dt
= 0
That's the right number, but is that the way to do it?