Why does my weight change when an elevator accelerates upward or downward?

Answer 1

Your weight doesn't change, rather your NEWTONS change!

Weight is a measure of the MASS of an object. Newtons are a measure of the FORCE being exerted on or by an object.

Speaking of Newton, Sir Isaac is the one who explained what happens on the elevator. According to him, an object at rest tends to stay at rest and an object in motion tends to stay in motion.

When you get into the elevator and the door closes, your body and the elevator are both stationary. Your body exerts pressure on the elevator equal to your weight.

As the elevator starts to accelarate upward, your body wants to stay put. As the elevator tries to pass your stationary body, the force of your body resisting the elevator increases. You still weigh the same because your mass hasn't changed, but the newtons of force pushing against the elevator increase.

As you continue up the shaft, your body very quickly matches the velocity of the elevator. Now, even though you're moving, the force of your body resisting the elevator is the same as when you were stopped.

When you start back down again, you simply go through the reverse process. As the elevator starts to drop, your body says "no thanks, I'm fine here." As the elevator accelerates away from your stationary body, the amount of force your body exerts on the elevator decreases. Soon, gravity says you're going with the elevator whether you like it or not and you match velocity with the elevator once again, bringing your "weight", or the force that you exert on the elevator based on your body mass and the pull of gravity, back to normal.

If you want a VERY simple demonstration of what happens on the elevator, go to the grocery store and toss a head of lettuce into the produce scale basket. Watch how the needle bounces up and down until it finally tells you how much the lettuce weighs. The bouncing needle shows the difference between weight (mass) and newtons (force).

Answer 2

Let's assume your body mass is M pounds and the acceleration due to garavity is g. Then your weight is M.g when you are standing still.

Now if the acceleration rate of the elevator is e then if you are going down an elevator your weight will be M.(g+e) and when you are going up will be M.(g-e) .

Note that M(g+e) > Mg > M(g-e) and that is why the change in weight. You feel heavier coming down and lighter when going up.

Note acceleration is a vector so when direction changes the relative acceleration will increase or decrese based on direction of 2 accelerations.

Answer 3

Mass and weight are different things, first off. (You will need to know that first. Your mass, very similar to weight, but not the same, is constant no matter where you are. Weight is a measure of the gravitational pull that is being exerted on you. The further away from the core of the object that is pulling you toward it, the less weight. Even though it is only a few floors in Earth's huge gravitational reach, there is still a tiny, unnoticeable difference. Any thing that you feel that feels like a change in weight is simply due to your stomach and other bodily sensations, not because of the change in weight, although there is a small change.

Answer 4

Yes, your weight changes when you accelerate up or down. Your mass does not change but your weight is a measure of the force your feet exert on the floor of the elevator. That force changes as the elevator accelerates.

Answer 5

Weight is the measure of the normal reaction force on your body. When going up in an elevator, the normal reaction not only supports your weight, but it also accelerates you upward. So the normal reaction is more than your own weight. Reverse while going down.

Answer 6

Your question contains your answer. It is the acceleration. Weight is a force which can be caused by gravity or by acceleration or both. Force equals mass times acceleration. When the elevator accelerates up, it adds a force to gravity. When it accelerates down, it subtracts a force from gravity.

Answer 7

Your mass changes, relatively. So yes, your weight changes under standard definition.

E=mc^2/(1-c^2/v^2)

As you change velocity your relative mass increases.

Meaning, you'll appear to have the same mass but you really don't. It's weird. Relativity at its best XD

Answer 8

your wieght does not change : when the elevator goes up it forces the body down because of the speed it is going up and when it goes down it lifts the body up because the box is falling at a high rate of speed .

Answer 9

Your weight stays the same, but the pressure your body exerts changes.

Answer 10

Due to inertia.