These work word problems will show how to calculate the work when the
force applied to the object and the displacement of the object
are known. You will therefore use the formula w = F × d
Problem #1:
How many joules of work are done against a cart when a force of 50 N pushes it 1 kilometer away?
Solution:
First convert 1 kilometer to meter. 1 kilometer = 100 meters.
Then, use the formula w = F × dProblem #2:
Work of 2000 J is required to push an object.
1) Give 2 examples of what F and d could be.
2) How much work is required to lift the same object if the distance pushed is 3 times bigger?
3) How much work is required if the force is doubled?
Solution
1) Examples of what F and d could be
F = 200 N and d = 10 meters
F = 20 N and d = 100 meters
F = 50 N and d = 40 meters
2) Pick F = 50 N and d = 40 meters.
If the distance is 3 times bigger, d = 3 times 40 = 120 meters
W = 50 N × 120 m = 6000 Joules3) Pick F = 200 N and d = 10 meters
If F is 2 times bigger, F = 2 times 200 = 400
W = 400 N × 10 m = 4000 JoulesProblem #3:
In a tug of war, team x pulled team y with a force of 10000 N a distance of 50 meters. Team y did not win because they were only able to exert of force of 8000 N. Calculate the work of each team.
Since the direction may or may not be the same, we will use the formula w = F × d × cos(x)Notice that the work is negative for team y.
This is going to be the case when the direction of the force is opposite to the direction of movement.
Jan 26, 23 11:44 AM
Jan 25, 23 05:54 AM