Al- Mabarrat Schools
Educational Institutes Board
Al- Hassan secondary School
Code: EIB-F127
IN HIS NAME
Physics: Mass and Weight
Grade 8
Ed:01
Mass and weight:
Mass Vs Weight
Mass
Weight
Definition
Quantity of matter in object
Force exerted by gravity on
object
Instrument used
Balance
Spring balance or
dynamometer
Unit
g or kg
Newton (N)
Changes with position
No
yes
Definition of weight
 Force acting from a distance.
 Force of attraction (Pull) exerted by the earth on all objects located in its gravitational field.
Characteristics:
Point of application: Center of gravity.
Line of action: Vertical
Direction: Downward
Magnitude: Can be measured using a spring balance or calculated using the formula.
G
G
𝐰
𝐰
G
𝐰
G
𝐰
Formula=
𝐰=𝐦×𝐠
 w = magnitude of the weight of the body in Newton [N]
 m = mass of the body in [kg]
 g = gravitational field strength “g = 9.81 N/kg”
Useful conversion: 1kg = 1000 g