In science, work is the amount of effort spent when a force causes an object to move a distance.
Examples of Work
An example of a person doing work is when you move a desk to another area. You are applying force on the desk that will cause the desk to move. This means that you are doing work on the desk.
When you are pushing on a wall, you are actually not doing any work. The wall doesn't move when you apply force to it. It is key that the object will move when you apply force to it or else you won't be doing work.
Calculating Work
Work can be calculated using the formula W = F x d. The variable "W" represents the work done on the object, the "F" is the force applied on the object which should be in newtons (N), and the "d" is the distance the object traveled which should be in meters (m). If the distance in the question is in cm, mm or any other unit for length, then you'll have to convert that measurement into metres or else your answer will be incorrect. Work and energy are both measured in the unit joules (J) so your answer should be in joules.
Examples of Calculating Work
1. Michael is lifting up a box to put it in his car. He lifts it with a force of 420 N and he lifted it 1.5 m high. How much work is he doing on the box? In this question, 420 N would be your "F" in the formula to calculate work because it is the force that is being applied on to the box. One point five metres would be your "d" because it is the distance that Michael is lifting up the box. Now you can just plug in your numbers in the formula W = F x d to find out how much work Michael is doing on the box:
W = F x d W = 420 x 1.5 W = 630 J
Michael did 630 J of work on the box. Notice how my answer was in joules. Remember don't forget that on the test or you can lose half a mark.
2.Ethan needs to lift an 11 kg gold bar 3 metres in the air to put it on the table. How much work is he doing on the gold bar? This question has a trick to it. It doesn't tell you the force it requires to lift it up into the air but it tells you the weight. To find the force, you can use the formula F = m x g that you might have learned in some other wiki. The variable "F" represents the force needed to move the object, "m" is the mass of the object you're moving which should be in kilograms (kg), and "g" is the gravitational constant which is 9.8 N/kg. If the mass of the object is in any other weight unit, then you'll have to convert to kilograms because the gravitational constant is 9.8 N/kg. The mass of the gold bar is 11 kg. Now you can plug in the numbers and use the formula to find the force:
F = m x gF = 11 x 9.8F = 107.8 N The force should always be in newtons. Now that you've found out the force, you can use the formula to find the work. The distance is 3 so you can plug the force and distance into the formula and solve: W = F x dW = 107.8 x 3W = 323.4 J Ethan did 323.4 J of work on the gold bar.
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Table of Contents
Definition
In science, work is the amount of effort spent when a force causes an object to move a distance.Examples of Work
An example of a person doing work is when you move a desk to another area. You are applying force on the desk that will cause the desk to move. This means that you are doing work on the desk.When you are pushing on a wall, you are actually not doing any work. The wall doesn't move when you apply force to it. It is key that the object will move when you apply force to it or else you won't be doing work.
Calculating Work
Work can be calculated using the formula W = F x d. The variable "W" represents the work done on the object, the "F" is the force applied on the object which should be in newtons (N), and the "d" is the distance the object traveled which should be in meters (m). If the distance in the question is in cm, mm or any other unit for length, then you'll have to convert that measurement into metres or else your answer will be incorrect. Work and energy are both measured in the unit joules (J) so your answer should be in joules.Examples of Calculating Work
1. Michael is lifting up a box to put it in his car. He lifts it with a force of 420 N and he lifted it 1.5 m high. How much work is he doing on the box?In this question, 420 N would be your "F" in the formula to calculate work because it is the force that is being applied on to the box. One point five metres would be your "d" because it is the distance that Michael is lifting up the box. Now you can just plug in your numbers in the formula W = F x d to find out how much work Michael is doing on the box:
W = F x d
W = 420 x 1.5
W = 630 J
Michael did 630 J of work on the box. Notice how my answer was in joules. Remember don't forget that on the test or you can lose half a mark.
2. Ethan needs to lift an 11 kg gold bar 3 metres in the air to put it on the table. How much work is he doing on the gold bar?
This question has a trick to it. It doesn't tell you the force it requires to lift it up into the air but it tells you the weight. To find the force, you can use the formula F = m x g that you might have learned in some other wiki. The variable "F" represents the force needed to move the object, "m" is the mass of the object you're moving which should be in kilograms (kg), and "g" is the gravitational constant which is 9.8 N/kg. If the mass of the object is in any other weight unit, then you'll have to convert to kilograms because the gravitational constant is 9.8 N/kg. The mass of the gold bar is 11 kg. Now you can plug in the numbers and use the formula to find the force:
F = m x gF = 11 x 9.8F = 107.8 N
The force should always be in newtons. Now that you've found out the force, you can use the formula to find the work. The distance is 3 so you can plug the force and distance into the formula and solve:
W = F x dW = 107.8 x 3W = 323.4 J
Ethan did 323.4 J of work on the gold bar.
Video explaining what work is
Link to YouTube: http://www.youtube.com/watch?v=qddydNEk-14