WHAT IS THE DIFFERENCE BETWEEN MASS AND WEIGHT ?  ARE THEY  USED AT DIFFERENT PLACES AND TIME?

1. Mass means how heavy somebody is in normal circumstances(i.e 1G) while weight is how heavy somebody is in relation to the force acting upon it i.e gravity.

2.Mass is uniform everywhere i.e your mass on earth will be the same as your mass on any other planet but your weight depends on how many G'^S are acting upon you.If your mass is 30kgs then in 1G^S your weight will be 30 kgs but in 0.5G^S your weight will be 15kgs but mass will stay the same.

3.The SI unit used for mass is kg while the SI unit for weight is kgf.

Mass is the amount of matter contained in a body and weight is the force by which the earth attracts a body toward its centre.

Mass of the body is the constant quantity and does not change with the change of position or location

Weight of the body is the  variable quantity and changes with the change in position and locationdue to the accelaration of the gravity acting on it.

Yes they are used at different places and time.

Mass is the quantity of matter present in a body and when we talk about Weight it is the force by which an object is attracted towards Earth.

mass remains constant througout the universe but mass varies from place to place

 mass remains constant throughout the universe whereas weight varies from place to place

mass is constant but weight is variable,its depend on gravity

 mass is the amount of matter in the body while weight is the gravitational force exerted on the body.That means if there is less gravitational force  than the weight is less and viceversa.

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