A horizontal force of 805 N is needed to drag a crate across a horizontal floor with a constant speed. You drag the crate using a rope held at an angle of 32 degrees.
a. What force do you exert on the rope?
b. How much work do you do on the crate when moving it 22m?
c. If you complete the job in 8 s, what power is developed?
Hope you guys can help me and explain to me how you got your solutions. Many thanks!
2007-02-21 13:42:37 · 3 answers · asked by Anonymous in Science & Mathematics ➔ Physics
Well....
a. First you do a free-body diagram... and you get the picture with a box and a force going 32 degrees above horizontal, you know you need a horizontal force of 805 N so you use Cos(theta)=F/805N so F=805cos(32) and there is your force.
b. W=F*D (dot product) so it is the horizontal component times the displacement. so it is the 805N * 22m ... which is also Fdcos(32)
c. Power is Work/Time so you take the amount of work done (part b) and divide it by 8 s and you get J/s which is Watts (power)
I assume this is for your HW, and i hope you understand for test sake
2007-02-21 14:20:15 · answer #1 · answered by Yowzers 2 · 1⤊ 1⤋
a)cos32=805/N
N=805/cos32
N=949.239N
b)w=fd
(only horizontal force)
w=805(22)
w=17710J
c)P=w/t
P=17710/8
P=2213.75watts
2007-02-21 14:37:20 · answer #2 · answered by climberguy12 7 · 2⤊ 0⤋
wouldn't you use
Acceleration????
A= Vf-Vi divided by T?
Or is it Velocity?
V-D over S?
Hope I helped.lol.
2007-02-21 13:58:23 · answer #3 · answered by Anonymous · 0⤊ 2⤋