What you would call the 'true weight', I suppose, is the reading of a set of scales on the surface of the Earth, if these scales are calibrated for the surface of the Earth.
You can just as well apply this ratio to the measured mass to find the true mass if you're actually using bathroom scales. While it is true that the gravitational force dissipates with respect to distance squared, that is not the reason a scale would output a "different weight".
A scale does not actually measure weight, only it's response to it. That is, the scale reads the normal force. If the elevator was motionless, the normal force would be equivalent in magnitude to your weight. Therefore, the scale reading would also happen to be your weight. Now consider an accelerating elevator. We can easily analyze what's going on mathematically. That is the normal force is the sum of your weight and the relative force associated with the accelerating elevator.
Physically, you can think about the electrons which account for the normal force in the scale. When the elevator is motionless or constant speed , and you are standing on the scale, those electrons will push back with equal force.
However, when the elevator is accelerating upward, those electrons are forced to be closer to your feet. The response then is simply a larger normal force. True weight actually the product of mass and gravitational acceleration which is equal to mg where the apparent weight is the sum of net forces when you standing in elevator and elevator is moving either upwards or downwards, either high speed or low speed then you feel your weight heavier or lighter this is the apparent weight that u feels which is equal to sum of net forces.
On the other hand when you jump from a certain height you feel weightless in that time no normal force present then net force 0 so that time apparent weight is zero.
In short apparent weight is the weight that you feel. Sign up to join this community. The best answers are voted up and rise to the top. Stack Overflow for Teams — Collaborate and share knowledge with a private group. Create a free Team What is Teams? Learn more. Trouble understanding the concept of true and apparent weight Ask Question.
Asked 7 years, 1 month ago. Active 5 years, 4 months ago. Viewed 46k times. Improve this question. ProfRob k 11 11 gold badges silver badges bronze badges. Strictly speaking, "weight" is just mass times force. Mass times force makes no sense. Add a comment. Active Oldest Votes. Improve this answer. John Red John Red 2 2 bronze badges. It's apparent weight! That value includes centrifugal acceleration term the centrifugal acceleration at 45 degrees latitude.
And you are wrong. David Hammen David Hammen Gaurav Gaurav 2, 1 1 gold badge 12 12 silver badges 30 30 bronze badges. Apparent weight can refer to different circumstances: If a mass is submerged in a fluid, i.
If you are a great distance from the center of earth, i. This is the most common reference. It involves the change in weight downward force when there is is a change in velocity in the vertical direction. A common example is the elevator example. If you stand on a scale in an elevator, your weight will appear, hence term apparent weight. An example: Get on an elevator and stand on a scale. Your weight will be same as in your bathroom. When the elevator accelerates upward, your weight will increase.
When it reaches its max velocity your weight will return to same as static weight, since there is no change in velocity. As it approaches your upper floor it will obviously have to slow down, and your weight will appear less than static weight.
The inverse is also true. If you enter the elevator on the th floor, and press ground floor, your weight will appear less until the elevator reaches its max velocity. An object in freefall can do no work because it is not exerting any downward Force. The only way a mass can exert an amplified Force, acting by gravity alone, is if it decelerates.
See also this related question Accelerating an elevator There are also plenty of other resources all over the internet - it's a fairly standard question. Community Bot 1. ProfRob ProfRob k 11 11 gold badges silver badges bronze badges. This person is standing on the surface of the Earth. Note that they are all the same length. The gravitational force on each one is the same. The compressions of the springs are not the same. The lower springs are compressed more than the higher springs because they have to exert more force on the lower masses.
Take the top mass assume all masses are 1 kg. So, for this mass to be in equilibrium, the spring must also push up with 9. If that spring connected the top mass and the next mass is the same spring, then this same spring should push DOWN on the next lower mass with 9.
So, the second lower spring would have to push up Since that spring must provide more force, it will be compressed more the more you stretch or compress a spring, the more force it exerts. Here is what that would look like: The red arrow represents the acceleration. Notice that the gravitational force is the same as it was before, but the springs are compressed more.
In this case, you would FEEL heavier. You are NOT heavier. Notice also that the blue arrow representing the force the floor pushes on the person is greater. Here you would feel lighter but you are not. Next case, accelerating down at 9. But here, there is NO force of the floor pushing on the person and the masses are equally spaced. This is because there is no need for the spring to exert a force on each mass since the following is true Since the acceleration is the same as the gravitational field g , no other force is needed to make it move this way.
Here you would feel weightless, but again - NOT. Ok, here is my final case. What if there was zero gravity as would happen if you were very far from any massive objects like planets or stars. Here is such a case: In this case, the masses seem to be compressed the same as they were with gravity, but no acceleration. But here there is no gravitational force.
How would this happen? If the floor is accelerating upwards at 9. Apparent weight is related to the force that is pushing on a person from an external object this is what you feel. Rhett Allain is an associate professor of physics at Southeastern Louisiana University.
He enjoys teaching and talking about physics. Image will be uploaded soon. You might already be aware that the earth attracts everybody towards its centre with some force of attraction known as the gravity force. Because of this force of gravity, all bodies experience their weight. But if the body is on a plane that is accelerated up or down, then the force deployed on the plane by the body i.
In such an instance, a person perceives his altered weight apparent weight. True or real weight simply is weight. So, what is your true weight? It's simply the mg. Mass multiplied by gravity. Apparent weight is represented by WA. It's described as;. That is simply away from the centre of the earth. You may be standing and someone may be attempting to push you horizontally. That normal force of reaction doesn't count.
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