How Much Work Does a Tow Truck Perform When Pulling a Car?

[magnifik]

Homework Statement

A tow truck drags a stalled car along a road. The chain makes an angle of 30 deg with the road and the tension in the chain is 1500 N. How much work is done by the truck in pulling the car 1 km?

Homework Equations

The Attempt at a Solution

What I'm confused about is whether we use W = FD or W=FDcos30
What I did was find the horizontal component of force (though I don't know if we use this or the tension given) F = 1500cos30=750*sqrt(3)
then i did W = FDcos30 = 750*sqrt(3)(1000)(cos30) = 1125000

Do i even put cosine again to find work?
Or can i just do W=FD
W=750*sqrt(3)(1000) = 1299038

 

[rock.freak667]

No the component of the force in the direction of motion is Fcosθ, so the work done is W=(Fcosθ)d, which is what you first did.