The document discusses the concept of force, defining it as a push or pull that causes changes in the motion or shape of objects. It highlights how forces can speed up, slow down, or alter the direction of moving objects through various examples like pushing a trolley or launching a rocket. Additionally, it includes interactive elements such as fill-in-the-blanks and questions about real-world applications of pushing and pulling forces.

1. What do you do to make a football move?
What do you do to make a moving ball move faster?
How does a goalkeeper stops a ball?
A hockey player changes the direction of ball with a
flick of stick.

2.  In all these situations either the ball is made to
move faster or is slowed down or its direction
is changed.
 Now the question arises what makes all these
changes?

3. FORCE AND
ITS EFECTS
CLASS-8
BY: SHILPA SINGH
ROLL NO: 10

4. FORCE
A Force is a Push or Pull or both. A force cannot be seen but we can
observe the effect of force.
Push Pull
Push
and
Pull

5. Pushing a car
Pushing a
trolley
Rocket
launching
PUSH: Push is the applied force which intend to
drive.

6. Tug of war Pulling a trolley
Pulling body weight
PULL: Action which acts in direction of the origin
of force.

7. Scrubbing the
floor Rowing the
boat
Playing guitar

8. Effects of
Force
Changes the
shape
temporarily
Changes the
shape
permanently
Change the
direction of
moving
object
Change the
speed of
moving
object
Stops a
moving
object or
makes a
stationary
object move

9. Pressing a sponge Squeezing a spring
Stretching a
rubber band

10. Breaking of glass
Crushing a can

11. Change in the direction of ball

14.  Fill in the blanks:
1. To move a loaded trolley we have to it.
2. To stretch a bow we need to it.
 Tell whether objects are pushed or pulled in the
following cases:
Raising a flag
Pressing a switch
Knocking a nail

15.  What is the action of force on objects when
1.A lump of dough is pressed down with hands.
2. Pulling the free ends of a
rubber suspended from a hook.
3. Hammering a piece of iron.

16.  Give two examples each of situations in which
you push or pull to change the state of motion
of objects.
 Give two examples of situations in which
applied force causes a change in the shape of
an object.