Question

You pull a 30.5 kg wooden box with a rope that makes a 23.0° angle with the horizontal at a constant speed. The coefficient of kinetic friction between the box and the deck is 0.330. You pull the crate a distance of 5.25 m. How much work was done?

Do you use f=ma and how does the angle get used in this equation?

Answer 1

work = force in the direction of motion
* distance

normal force down = weight - tension component up

= m g - F sin 23

friction force = .33(mg-F sin 23)

drag force = F cos 23

no accelration so friction force = drag force

F cos 23 = .33 (mg-F sin 23)

solve for F
we want the horizontal component of F
for the work
work = F cos 23 * 5.25
the end

Answer 2

By the way is a physic something you take for a stomach ache?

Answer 3

http://www.thefreedictionary.com/physic