Talia's winch tows a crate across a yard with a steady 50 N force, in the crate's direction of motion. The winch's work on the crate comes to 200 J.
No distance is given. Can the work equation hand it back?
The multiply runs in reverse. Work is force times distance, so the distance is the work shared out over the force.
Divide the work by the force: 200 ÷ 50 = 4. The crate moved 4 m.
Time for symbols. Work gets the capital letter W, and the equation is W = Fd.
Capital W is work, measured in joules. It is not the lowercase w you met for weight, where w = mg. When a problem needs work and weight together, this course writes weight out in words.
To find the force, divide the work by the distance: F = W/d.
To find the distance, divide the work by the force: d = W/F.
In this lesson every force acts with the motion, so W stays positive throughout.
A rope does 180 J of work towing a go-kart 12 m, the force acting with the motion. Calculate the force.
Write down the values:
W = 180 J, d = 12 m, F = ?
Write down the equation:
F = W/d
Substitute in the values, and calculate:
F = 180 ÷ 12 = 15
The force is 15 N.
A forklift's lifting force of 300 N does 240 J of work on a pallet. Calculate the distance the pallet rises.
Write down the values:
W = 240 J, F = 300 N, d = ?
Write down the equation:
d = W/F
Substitute in the values, and calculate:
d = 240 ÷ 300 = 0.8
The pallet rises 0.8 m.
Ugo knows the work a rope did on a wagon and the force it applied, both with the motion. Which arrangement gives the distance the wagon moved?
The same wagon: the rope does 96 J of work with a 16 N force. Enter the distance the wagon moves in m.
A cable tow does 275 J of work on a ski trainee over 5 m, the force acting with the motion. Enter the force in N.
A luggage belt's force of 32 N, acting with the motion, does 272 J of work on a duffel bag. Enter the distance the bag rides in m.
Romy knows the work W a sled tow did on a sled and the distance d the sled moved. How does she calculate the force?
A stage crew's hoist rope, acting with the motion, does 414 J of work raising a scenery flat through 4.6 m. Enter the force in N.