force and laws of motion 89

1. Ch 2 Force and laws motion

2. force:- • A push or pull on a body is called force • forces are used in our everyday actions like pushing,lifting,stretching,twisting and pressing

3. Effects of force • Force can move a body on rest • Force can stop a moving body • Force can change the speed of the moving body • Force can change the direction of the moving body • Force can change the shape and size of the moving body

4. Balanced force • Balanced force:if the resultant of all the forces acting on a body is zero,the forces are called balanced forces • Balanced force cannot change the state of rest or motion of a body

5. Unbalanced force • If the resultant of all the forces acting on a body is not zero,the forces are called unbalanced forces • Unbalanced forces changes the state of rest or the motion of a body

6. Isaac newton:-

7. Newton’s first law of motion • Newton’s first law of motion states that :-an object remains in a state of rest or in uniform motion in a straight line unless compelled to change that state by an applied force • Inertia:- inertia is that property of a body due to which it resists a change in its state of rest of uniform motion

8. examples of inertia:- • If a car or any other vehicle starts • Falling a coin into glass

9. momentum • The momentum of a body is the product of its mass and velocity. • momentum=mass x velocity • p=mv • If the body is at rest its velocity is zero and so its momentum is also zero • The SI unit of momentum is kelogram meter per second or kg m/s

11. Newton’s third law of motion • Newton’s Third Law of Motion states: ‘To every action there is an equal and opposite reaction •  For example, when we placed a wooden block on the ground, this block exerts a force equal to its weight, W = mg acting downwards to the ground.

12. Made by :- Shagunsanghi IX