1. Work is defined as the product of the force exerted on an object and the distance the object is displaced in the direction of the force. 2. Work is done when a force causes an object to move in the direction of the applied force, such as a girl pushing a chair. No work is done if there is no displacement in the direction of the force, such as a boy pushing a wall. 3. Work can be calculated using the formula W=Fd, where W is work in Joules, F is force in Newtons, and d is distance in meters. The document provides examples of calculating work done by various forces over different distances.

1. WORK
Grade 8 Science

2. 3. Explain how work is related to
energy;
4. Compute work done by a constant
force.
1. Define work scientifically;
2. Identify situations in which work
is done and in which no work is
done;
OBJECTIVES

3. WORK
What is it?

4. • It is scientifically defined as the
product of the force exerted on an
object and the distance the object
moved to the direction of the force.
WORK
W=Fd
Where: W=work
F=Force
d=distance/displacement
work =
Amount of force applied
In the direction of motion
Distance over which the
force is applied
x

5. WORK
A girl pushing a chair
Is there any work done?
YES,
there is work done.

6. WORK
Is there any work done?
No,
there is no work done.
A boy pushing a wall

7. WORK
Is there any work done?
No,
there is no work done.
A waiter carrying a tray

8. Work is done on an object when the force applied to it
covers a distance in the direction of the applied force.
Work is done
No Work is done
No Work is done
WORK

9. WORK
Is there work done?

10. Calculating a Work
WORK
Work is done when the force (F) applied to the object causes the object to
have a displacement (d) in the same direction as the force applied.
W=Fd Where: W=work
F=Force
d=distance/displacement

11. WORK
Unit for Work
James Prescott Joule
One (1) Joule is equal to the work
done or energy expended in
applying a force of one Newton
through a distance of one meter.

12. WORK
Suppose a woman is pushing a grocery cart with a 500 Newton
force along the 7 meters aisle, how much work is done in
pushing the cart from one end of the aisle to the other?
Given:
Required:
Formula:
Solution:
F = 500 N
d = 7 m
W = ?
W = Fd
W = 500 N (7m)
W = 500 Nm
W = 3500 J

13. WORK
Suppose a woman is pushing a grocery cart with a 500 Newton force
along the 7 meters aisle, how much work is done in pushing the cart
from one end of the aisle to the other?
Supposing that a woman is having different amount of forces applied in
pushing the grocery cart with distinct distances. How much is the work?
Group 1
Fore = 350 N
Distance = 6 m
Group 2
Force = 700 N
Distance = 9.2 m
Group 3
Force = 156 N
Distance = 2.6 m
Group 4
Force = 875 N
Distance = 14 m
W=Fd