General doubt,

When you body part is moving head ,hand or anything ,your centre of mass is in motion and bcz of this the normal for acting on your body will not be equal to you weight . Remembe...

weight will not change when we bend our head because weight is simply mass multiplied by acceleration due to gravity between our feet and weighing machine..

if you bend your head such that centre of mass of your body is still above the weighing machine, then there would be no significant change. but if centre of mass is shifted such th...

it's depending on the centre of mass. if we move any body part cm shifts then reading changes in fraction of time after that it's reading stable.