Force and Law of Motion
Introduction of Force :- It is push or pull on any object. It
may change the position of object. Object in rest can start moving, moving
object can stop, it may change it’s structure, It can change the direction of
object, on applying an external force.
 |
| science-ncert-solution |
Example :- 1. A box is on the floor in rest position, is
start moving only when we apply an external force on it.
2. A moving object does not stop even when we apply an
external force.
3. The contact of bat and ball. When bat and ball in
contact, the direction of the ball changes due to external contact force.
Effect of force
1. Force can change the position of moving object.
2. A object in rest can start moving.
3. It can change the direction of motion of any object.
4. It can joint two bodies or objects.
5. It can break any object.
6. It can change the shape of object.
Definition of Force :- The factor that can create the motion
in any object or oppose the motion of body or object, known as Force.
Contact Force :- If the two bodies or objects are in
physical contact then the force is known as Contact Force.
Example :- The contact of hockey stick with ball.
Non-Contact Force :- If the two bodies or object are not in
physical contact then the force is known as Non-Contact Force.
Example :- Force between Moon and Earth.
Internal Force :- If a body exert force on its one part to
another part internally, known as Internal Force.
Example :- Attraction force between Electrons.
External Force :- A force exerted by any object to other
object externally, known as External Force.
Example :- Screw driver with screw.
Balanced Force :- The algebraic sum of all the force exerted
on an object or body is zero, known as balanced force.
Example :- The car parked in parking.
Unbalanced Force :- The algebraic sum of all the force
exerted on an object or body is not zero, known as balanced force.
Example :- The moving car on the road.
Motion :-
If a body or object changes its position from one point to other point with reference
point, is said in Motion.
For Example :- Train running from Delhi to Mumbai. In this case
the reference point of train is Delhi but train now running to Mumbai so train
is said in motion.
Types of Motion
1. Linear Motion :- If a body or object is moving in a straight line path,
the motion is said to be ‘Linear Motion”
For example :- A car is running on straight highway.
2. Circulatory Motion :- If a body or object is moving in a circular path, the
motion is said to be ‘Circulatory Motion”
For example :- The motion of earth around the Sun.
3. Oscillatory Motion :- If a body or object is moving in left or right direction
from its middle point, the motion is said to be ‘Oscillatory Motion”
Note 1 :-
In this year we only study about Linear Motion.
 |
| science-ncert-solution |
Laws of Motion
1. First Law of Motion :- Any body or object does not changes its
position of rest or motion unless a external
force is not applied.
Example :- In a moving car, if break is applied, person sitting in
it pull backward.
2. Second Law of Motion :- The rate of change of momentum is directly
proportional to force. The direction is same as the direction of force.
3.Third Law of Motion :- If a body exert a force on any object then
the object is also exerting an force on that body. This is also known as action
and reaction force.
We can say that every action have equal and opposite reaction.
Example :- 1. Hit on table we also feel that contact force on our
hand.
2. Every body have its weight downward, but due weight a reaction
force generated upward direction.
Inertia :- Inertia is the property of object which oppose the position
of uniform motion or rest.
 |
| science-ncert-solution |
Kinds of Inertia :-
1. Inertia of Rest :- The property of object by which it oppose
the position of rest, known as inertia of rest.
2. Inertia of Motion :- The property of object by which it oppose
the position of uniform motion, known as inertia of motion.
3. Inertia of direction :- The property of object by which it
oppose the change in direction, means to say that it wants to remains its
original direction.
Conservation of Momentum
If the two objects collide with each other, the total momentum
of objects before the collision is equal to the total momentum after collision.
m1 * v1 = - m2 * v2 ( - sign showing opposite direction of
object )
 |
| science-ncert-solution |
Conservation of Linear momentum
According to second law of motion, the force acting on any
object or body is equal to rate of change in momentum of object or body.
F = dp / dt
If there are no external force exerted on body or object. So
F = 0
dp / dt = 0
P = constant
or m * v = constant
m1 * v1 = m2 * v2
Hi. I’m Designer of Blog Magic. I’m CEO/Founder of ThemeXpose. I’m Creative Art Director, Web Designer, UI/UX Designer, Interaction Designer, Industrial Designer, Web Developer, Business Enthusiast, StartUp Enthusiast, Speaker, Writer and Photographer. Inspired to make things looks better.
0 comments:
Post a Comment