Points to Remember

Laws of Motion (Science)

Points to Remember

·                 Mechanics is divided into statics and dynamics.

·                 Ability of a body to maintain its state of rest or motion is called Inertia.

·                 Moment of the couple is measured by the product of any one of the forces and the perpendicular distance between two forces.

·                 SI unit of force is newton (N). C.G.S unit is dyne.

·                 When a force F acts on a body for a period of time t, then the product of force and time is known as ‘impulse’.

·                 The unit of weight is newton or kg f

·                 The weight of a body is more at the poles than at the equatorial region.

·                 Mass of a body is defined as the quantity of matter contained in the object. Its SI unit is kilogram (kg).

·                 Apparent weight is the weight of the body acquired due to the action of gravity and other external forces on the body.

·                 Whenever a body or a person falls freely under the action of Earth’s gravitational force alone, it appears to have zero weight. This state is referred to as ‘weightlessness’.