Understanding Work in Physics

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Work
 
 
What do you think of when
you think of work?
 
You probably
think of…
 
In physics…
 
Work
 is performed when a force that is
applied to an object moves that
object.
 
When is work done?
 
The 
force and
motion 
of the object
have to be in the
same direction
.
There must be some
movement in the
direction of the
force
.
 
No work is done on
the bin because force
and motion are in
different directions.
 
Work is done on the
bin because force
and motion are in the
same direction.
Formula
Work = Force x Distance
The unit of force is 
Newtons
 (N)
The unit of distance is 
meters
 (m)
The unit of work is 
Newton-meters
 (N m)
One Newton-meter is equal to one joule
So, the unit of work is a 
joule
 (J)
Thus, work depends on…
 
Force
The 
larger
 the applied force, the 
more
 work
is being done.
The 
smaller
 
the applied force, the 
less
 
work is
being done.
 
Distance
The 
further
 an object is moved, the 
larger
 the
work required.
The 
shorter
 
the object is moved, the 
smaller
the work required.
 
Force
 
Distance
 
Suppose you want to get to the top of
a hill. Which path will require the least
amount of work to get to the top?
 
Path A
Walking up the long hill
 
Path B
Climbing up the
steep hill
If you chose path A… then you are wrong!
If you chose path B… then you are also wrong!
 
Both paths require the
same
 amount of work
to get to the top.
How is this possible?
Work
Force
Distance
Path B, while shorter,
requires more force
(than A)against the
gravity to reach the
top.
Path A, while longer,
requires less force
(than B) against gravity
to reach the top.
Work
Force
Distance
 
Both paths require the 
same
amount of work to get to the top.
Let’s look at another example.
An inclined ramp at different angles: 30°, 45°, 60°
Observe what happens to work (bottom row) as the car
reaches the same height with the different sloped ramps.
 
The car must use a greater force to move up against gravity.
The greater the incline the less distance the car must travel.
Work Example 1
You are leaning on a box with a force of 20
Newtons (N) but the box doesn’t move.
How much work is done?
 
W = F x D
 
W= 20 N x 0 m
 
W= 0 Joules
No work is done on the box!
Work Example 2
You lift a box  with 10 Newtons of force
onto a moving truck that is 1.5 meters
high.  How much work did you do?
 
W = F x D
W= 10 N x 1.5 m
W= 15 Joules
o
It takes 5 Newtons of force to push the same
box onto a moving truck using a ramp that is 3
meters long. How much work did you do?
(Assuming no friction on the ramp)
Work Example 3
 
W = F x D
W = F x D
W= 5 N x 3 m
W= 5 N x 3 m
W= 15 Joules
 
The 
The 
same amount of  work 
same amount of  work 
is done but the
is done but the
ramp makes the work easier due to
ramp makes the work easier due to
distribution of force.
distribution of force.
 
As you saw from the previous
examples:
 
If you move the 
SAME
 object to the 
SAME
location, it is the 
SAME WORK
!
 
Summary
 
Work
 is performed when a force applied to an
object moves the object.
The 
force and motion 
of the object have to be
in the 
same direction 
for work to be done.
There must be some 
movement in the
direction of the force
.
Work depends on 
force
 and 
distance
.
No work is done on an object when it is at rest.
Displacing the same object to the same
location results in performing the same
amount of work.
 
Calculating Work Tips
 
Read the question carefully to identify what you
need to solve for and what is given to you.
 
Every answer should have the units included.
 
The shorthand for the unit 
meters
 is written as 
m
 and
Newtons is 
N
.
 
Work in a step by step manner by writing each step
out.
 
The Work Equation can be rearranged to solve for
different things.
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Exploring the concept of work in physics, this content covers how work is performed, when it is done, and the formula to calculate work based on force and distance. It highlights that the amount of work depends on the force applied and the distance moved, showcasing that different paths may require the same amount of work despite variations in length and steepness.


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  1. Work

  2. What do you think of when you think of work? think of You probably

  3. In physics Work is performed when a force that is applied to an object moves that object.

  4. When is work done? The force and motion of the object have to be in the same direction. There must be some movement in the direction of the force. Work is done on the bin because force and motion are in the same direction. No work is done on the bin because force and motion are in different directions.

  5. Formula Work = Force x Distance The unit of force is Newtons (N) The unit of distance is meters (m) The unit of work is Newton-meters (N m) One Newton-meter is equal to one joule So, the unit of work is a joule (J)

  6. Thus, work depends on Work = Force x Distance Force Distance Force The larger the applied force, the more work is being done. The smallerthe applied force, the lesswork is being done. Distance The further an object is moved, the larger the work required. The shorterthe object is moved, the smaller the work required.

  7. Suppose you want to get to the top of a hill. Which path will require the least amount of work to get to the top? Path B Climbing up the steep hill Path A Walking up the long hill

  8. If you chose path A then you are wrong! If you chose path B then you are also wrong! Both paths require the same amount of work to get to the top.

  9. How is this possible? Path A, while longer, requires less force (than B) against gravity to reach the top. Path B, while shorter, requires more force (than A)against the gravity to reach the top. Work Work Force Force Distance Distance Both paths require the same amount of work to get to the top.

  10. Lets look at another example. An inclined ramp at different angles: 30 , 45 , 60 Observe what happens to work (bottom row) as the car reaches the same height with the different sloped ramps. The car must use a greater force to move up against gravity. The greater the incline the less distance the car must travel.

  11. Work Example 1 You are leaning on a box with a force of 20 Newtons (N) but the box doesn t move. How much work is done? W = F x D W= 20 N x 0 m W= 0 Joules No work is done on the box!

  12. Work Example 2 You lift a box with 10 Newtons of force onto a moving truck that is 1.5 meters high. How much work did you do? W = F x D W= 10 N x 1.5 m W= 15 Joules

  13. Work Example 3 o It takes 5 Newtons of force to push the same box onto a moving truck using a ramp that is 3 meters long. How much work did you do? (Assuming no friction on the ramp) W = F x D W= 5 N x 3 m W= 15 Joules The same amount of work is done but the ramp makes the work easier due to distribution of force.

  14. As you saw from the previous examples: If you move the SAME object to the SAME location, it is the SAME WORK!

  15. Summary Work is performed when a force applied to an object moves the object. The force and motion of the object have to be in the same direction for work to be done. There must be some movement in the direction of the force. Work depends on force and distance. No work is done on an object when it is at rest. Displacing the same object to the same location results in performing the same amount of work.

  16. Calculating Work Tips Read the question carefully to identify what you need to solve for and what is given to you. Every answer should have the units included. The shorthand for the unit meters is written as m and Newtons is N. Work in a step by step manner by writing each step out. The Work Equation can be rearranged to solve for different things. Force x Distance Work = Work Force = Distance Work Force x Distance Work = Distance = Force

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