Work is the transfer of energy from one object to another, in order to make the second object move in a certain direction.
In science, work is the amount of effort spent when a force causes an object to move a distance.
Example 1: When you kick a ball,your foot is exerting energy on the ball causing it to move a distance. This means that you are doing work.
Example 2:When you are pushing a wall, you are actually not doing any work! For work to be done it requires an object that will move when you apply force to it, or else you won't be doing work.
How to calculate work
Work can be calculated by using the formula W= Fd. Work is always measured in the same units as energy which is the joules (J), which is represented by the variable W in the formula. The variable F represents the amount of force applied on the object which is in newtons, and the variable d is the distance the object moves, which is measured in meters. (If it is cm,mm,etc it should always be converted to meters).
(Work)
(Force in newtons) x (distance in meters)
or
Work
Force x Distance
When ever the object is in kg and you are not given the force, you can use the formula "F
mg" The Variable "F" is the force need to move the object, the variable "m" is the mass of the object being moved (which should be in kilograms,kg) and the variable "g" is the gravitational constant which is 9.8 N/kg. =
Examples of Calculating Work
1. James and his family are moving houses. James is trying to lift a box, he lifts with a force of 5N and he lifted it 1m high.
How much work is he doing on the box?
In this question, 5N would be the "F" in the formula "W=Fd", because it is the force that is being applied on the box. 1m would be the "d" in the formula, because it is the distance that James is lifting up the box.
Answer: W= Fd
= 5N x 1m
= 5 J
Michael did 5 J of work on the box.
Example 2:
Sarah is helping her parents by cleaning out the attic. Sarah is trying to lift a 50N box to a height of 3 m.
How much work is Sarah doing on the box?
In this question 50N is the force that is being applied on the box which represents the "F" in the formula "W=Fd" , and 3m is the distance Sarah is lifting up the box which is represented by the variable d.
Answer: W =Fd
= 50 x 3
= 150 J
Sarah did 150 J of work on the box.
Example 3:
Stephen did a total of 300 J of work lifting up a box. He lifted the box up 2 meters into the air to put it in his car. How much Force was being applied to the box?
In this question, we have the total work done, which is the "W" in the formula "W=Fd", and the distance which the box was lifted, which is the "d". Since we don't have the Force we must rearrange the formula and plug in the numbers.
To find the force, we have to rearrange the formula to express "F" in terms of "W".
Instead of
W=Fd
"F" would equal "Work" divided by "distance.
F=W/d
F=W (divided by) d
F=W/d
=300/2
=150 N
There was a total of 150 N being applied onto the box.
Example 4
Faye needs to lift a 10 kg box, 4 m in the air to put it on the table.
How much work is she doing on the bag?
F=mg
=10 x 9.8
= 98 N
W=Fd
= 98 x 4
=392 J
Faye did 392 J of work on the box.
Just like example 3 , you can rearrange the formula in many different ways to solve each variable.
Work
Definitions:
Work is the transfer of energy from one object to another, in order to make the second object move in a certain direction.
In science, work is the amount of effort spent when a force causes an object to move a distance.
Example 1: When you kick a ball,your foot is exerting energy on the ball causing it to move a distance. This means that you are doing work.
Example 2: When you are pushing a wall, you are actually not doing any work! For work to be done it requires an object that will move when you apply force to it, or else you won't be doing work.
How to calculate work
Work can be calculated by using the formula W= Fd. Work is always measured in the same units as energy which is the joules (J), which is represented by the variable W in the formula. The variable F represents the amount of force applied on the object which is in newtons, and the variable d is the distance the object moves, which is measured in meters. (If it is cm,mm,etc it should always be converted to meters).
(Work)
(Force in newtons) x (distance in meters)
or
Work
Force x Distance
When ever the object is in kg and you are not given the force, you can use the formula "F
mg" The Variable "F" is the force need to move the object, the variable "m" is the mass of the object being moved (which should be in kilograms,kg) and the variable "g" is the gravitational constant which is 9.8 N/kg. =Examples of Calculating Work
1. James and his family are moving houses. James is trying to lift a box, he lifts with a force of 5N and he lifted it 1m high.
How much work is he doing on the box?
In this question, 5N would be the "F" in the formula "W=Fd", because it is the force that is being applied on the box. 1m would be the "d" in the formula, because it is the distance that James is lifting up the box.
Answer: W= Fd
= 5N x 1m
= 5 J
Michael did 5 J of work on the box.
Example 2:
Sarah is helping her parents by cleaning out the attic. Sarah is trying to lift a 50N box to a height of 3 m.
How much work is Sarah doing on the box?
In this question 50N is the force that is being applied on the box which represents the "F" in the formula "W=Fd" , and 3m is the distance Sarah is lifting up the box which is represented by the variable d.
Answer: W =Fd= 50 x 3
= 150 J
Sarah did 150 J of work on the box.Example 3:
Stephen did a total of 300 J of work lifting up a box. He lifted the box up 2 meters into the air to put it in his car. How much Force was being applied to the box?
In this question, we have the total work done, which is the "W" in the formula "W=Fd", and the distance which the box was lifted, which is the "d". Since we don't have the Force we must rearrange the formula and plug in the numbers.To find the force, we have to rearrange the formula to express "F" in terms of "W".
Instead of
W=Fd
"F" would equal "Work" divided by "distance.
F=W/d
F=W (divided by) d
F=W/d
=300/2
=150 N
There was a total of 150 N being applied onto the box.
Example 4
Faye needs to lift a 10 kg box, 4 m in the air to put it on the table.
How much work is she doing on the bag?
F=mg
=10 x 9.8
= 98 N
W=Fd
= 98 x 4
=392 J
Faye did 392 J of work on the box.
Just like example 3 , you can rearrange the formula in many different ways to solve each variable.
To find Work (J)
The formula is
W=Fd
To find Force (F)
The formula is
F=W/d
To find distance (d)
The formula is
d=W/F
Work Videos
Introduction to work and energy: Introduction to work and energy
Click on the links below to view the other wikis.
Homepage ~ Energy ~ Work ~Practice quiz ~ Quiz answers >>>>> links