# What forces act on an elevator?

The combined system of you + elevator has two forces, a combined force of gravity and the tension in the cable. Consider the normal force acting on you from the elevator: N = mg if the elevator is at rest or moving at constant velocity. N = mg + ma if the elevator has an upward acceleration.

## Are you heavier or lighter in an elevator?

If you stand on a scale in an elevator accelerating upward, you feel heavier because the elevator’s floor presses harder on your feet, and the scale will show a higher reading than when the elevator is at rest. On the other hand, when the elevator accelerates downward, you feel lighter.

## Why does a person in a free falling elevator feel weightless?

When in free fall, the only force acting upon your body is the force of gravity – a non-contact force. Since the force of gravity cannot be felt without any other opposing forces, you would have no sensation of it. You would feel weightless when in a state of free fall.

## How do you calculate work done by an elevator?

The work done by the elevator over the 100 meters is easily calculable: W = mgh = (1000)(9.8)(100) = 9.8×105 Joules. The total time of the trip can be calculated from the velocity of the elevator: t = = = 25 s.

## Does gravity affect elevators?

From Newton’s second law F=ma, acceleration requires a force proportional to mass. So when the elevator is accelerating upwards, it must not only oppose gravity but provide extra force for the upward acceleration. This requires an increased normal force.

## What Newton’s law is an elevator?

This is an application of Newton’s second law to the forces felt in an elevator. If you are accelerating upward you feel heavier, and if you are accelerating downward you feel lighter. If the elevator cable broke, you would feel weightless since both you and the elevator would be accelerating downward at the same rate.

## What is the acceleration of an elevator?

“For example an observer in an elevator going upward with an acceleration equal to that produced by the gravitational pull of the Earth would see any object that was dropped fall to the floor of the elevator as exactly the same way that it would fall to Earth.” 9.8 m/s2.

## Where in an elevator do you feel heaviest?

If you stand on a scale in an elevator accelerating upward, you feel heavier because the elevator’s floor presses harder on your feet, and the scale will show a higher reading than when the elevator is at rest. On the other hand, when the elevator accelerates downward, you feel lighter.

## Why do I feel light in an elevator?

This can also make you feel lighter: when the elevator slows down, you need to slow down with it. But gravity is always pulling you down, so for you to slow down, the floor needs to push up on you less, so gravity can slow you down. Since the floor pushes on you less, you feel lighter.

## Is free fall the same as zero gravity?

Wait, so weightlessness is just free fall? Yes. Free fall is defined as “any motion of a body where gravity is the only force acting upon it.” In the vacuum of space, where there are no air molecules or supportive surfaces, astronauts are only acted upon by gravity.

## At what height does weightlessness occur?

Any object that is falling freely is weightless, no matter where it happens to be. This can be the International Space Station at a height of 200 miles, a NASA reduced-gravity airplane at a height of several thousand feet, a drop tower at several hundred feet, or you jumping off a chair at 3 feet.

## Does weight change in an elevator?

When the elevator is moving, we will weigh our normal weight. Since we are already moving at the same speed as the elevator (up or down), nothing is affecting us to change our weight. However, when the elevator starts to go or stops, our body resists it.

## How much work does an elevator motor do to lift a 1000 kg elevator a height of 200 m?

Thus, the work done is 9.81×105J.

## How fast can an elevator accelerate?

The fastest installed elevator reaches speeds of 67 feet per second (20.5 meters per second), or 46 miles per hour (73.8 kilometers per hour) in the Shanghai Tower.

## How do you calculate acceleration of an elevator?

1. Where EA is the Elevator Acceleration (m/s^2)
2. T is the tension force of the elevator motor (N)
3. m is the elevator mass (kg)
4. g is the acceleration due to gravity ( 9.81 m/s^2)

## What happens to your weight when the elevator starts moving and why?

When an elevator starts to accelerate upwards, you and your scale experience the same acceleration. The floor of the elevator pushes you and the scale upwards. This means the scale has to push on the person with an extra force to push you and your weight up too.

## When lift is going down with acceleration?

Case 2: If the lift is going down with acceleration a. Apparent weight, R = m( g – a ). And as the lift accelerates downwards, the man’s apparent weight within it diminishes if a value increases and is more than g then the man’s apparent weight inside the lift is negative.

## Is upward acceleration positive or negative?

So, if an object is moving vertically upwards, the direction of motion is positive for upwards journey. Hence, the acceleration due to gravity is taken as negative as its direction is downward.

## How heavy is an elevator?

Weight Capacity- The weight of an Automobile Elevator starts at 6,000 lbs. and can go up to 20,000 lbs.

## What would happen if an elevator fell?

Expect a broken leg or two, but you’ll live. (Some have suggested lying down in the lift, because it will distribute the force of impact over your whole body. This is a terrible idea – protect your brain! Some part of your body must absorb the impact, but head injury is the primary cause of death in falls.

## Which law is used in escalator?

Accelerometers, forces and Newton’s second law.