physics
posted by Sasha on .
When will your apparent weight be greatest, as measured by a a scale in a moving elevator; when the elevators: (a) accel. downward (b) accel. upward (c) is in free fall (d) moves upward at a constant speed? In what case would you weight be the least? When would it be the same as when you are on the ground?

Think about it.
weightapparent=mg+ma where a is up. What if a is down? What if a=g? 
Apparent weight
= m(g+a)
where g=9.8 m/s²
a=acceleration, positive upwards.
(a) W=m(ga)
(b) W=m(g+a)
(c) W=m(gg) = 0
(d) W=m(g+0) = mg 
so the it would be the least on the way down, b/c your force, pushing on the scale is less. And it is greatest on the way up, since your force of push is stronger. And I would say in free fall it is the same as ground state?

Rethink freefall.

ohh okay so the weight would be the same on the ground if its moving up at a constant speed?

Exactly. When it moves upwards (or downwards) at a uniform velocity, the reaction on the floor is the same as the weight. You have probably experienced this when you ride on an elevator.

sweet!! thank you =)

You're welcome!