we know that , weight of an object is given as
W = mg
where W = weight , m = mass of the object and g = acceleration due to gravity at that place.
An astronaut travels from the earth to the moon :
as the astronaut travels from the earth to the moon, the mass of astronaut stays the same but the weight change as acceleration due to gravity change since acceleration due to gravity on moon is only 1/6 times that on earth.
A child grows taller :
as child grows taller , he gains body mass . hence both mass and weight change.
An overweight person goes on a diet :
as an overweight person goes on diet , he loose body mass . hence both mass and weight change.
A snowball rolls downhill and picks up snow making it grow :
As snowball rolls downhill , it gains snow, hence its mass and in turn the weight change.
