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# Mass and Weight

Rural Technology

Generally, mass is defined as the measure of how much matter an object or body contains. It is measured in Gram (g).

Weight is the amount of force that earth exerts on us. More the mass of object more is the gravitational force on the object. If we drop an object from a height, earth pulls it at the acceleration of 9.8m/s2

Acceleration is the rate of change of speed. This means speed of an object will increase by 9.8m every second. This means, if an object falls from a height to reach earth, after 10 second it would have achieve speed of 9.8 ×10 = 98 m/s. · Force causes acceleration, Sir Isaac Newton’s Second Law states that the acceleration (a) of an object is directly proportional to the force (F) applied, and inversely proportional to the object’s mass (m) Newton’s Second Law is usually summarized in equation form: a = F/m, or F = ma Unit of force is derived as follows - Unit of force F = m (Kg) × a (m/s2) = Kg m/s2 = N

To honor Newton’s achievement, the standard unit of force i.e kg m/s2 in the SI system is named as Newton (N). One Newton (N) of force is enough to accelerate 1 kilogram (kg) of mass at a rate of 1 meter per second square (m/s2). A kilogram is the amount of weight at which 1 N of force will accelerate at a rate of 1 m/s2. In practice, we measure weight, in terms of gms. or Kgs. But when weight is used as force, we must remember to measure it in terms of Newton.

## Intext Questions

Fill in the blanks: i) is the rate of change of speed. ii) Weight is measured in grams, but when weight is used as force, we measure it in terms of .

Rural Technology