Physics of Elevator: Will Inertia Allow a Person to Touch the Roof?

In summary, the argument discussed whether a person in a falling elevator would touch the roof without any external force or if they would simply feel weightless. The conclusion was that in a real elevator, emergency brakes would prevent free fall and in the scenario without brakes, the person would feel weightless but not fly up to the ceiling due to inertia and the force of pushing against the floor before the cable snapped.
  • #1
frankenkash
1
0
This, in my opinion, is a no-brainer. But i decided to post this as a confirmatory proof to a friend who refuses to see reason!

The argument: In an elevator whose cable has snapped, irrelevant of whether it's stationary or going up/down, the person inside will travel upwards in the falling lift to hit the roof. Now i hope i have not changed the context of this question or changed how it was stated, but I would like to ask- WILL A PERSON IN A FALLING ELEVATOR EVER TOUCH THE ROOF (without jumping/external force) DUE TO INERTIA OR ANY OTHER SUCH FORCE? Or would he just feel weightless from the second the cable snaps to the time the thing touches bottom... (lets not bring in practical forces such as wind resistance etc etc)
 
Physics news on Phys.org
  • #2
If you're in an elevator and the cable snaps so that you and the elevator are in free fall, then you'll feel weightless. You won't magically fly up to the ceiling. (Of course real elevators have emergency brakes.)
 
  • #3
You were pushing against the floor with your legs, before the cable snapped, and you will get some upwards velocity (relative to te elevator), since you can't stop pushing immediately.
Of course you'll lose contact with the floor very quickly, so you won't get a lot of velocity.
 

Related to Physics of Elevator: Will Inertia Allow a Person to Touch the Roof?

1. How does the physics of an elevator allow a person to touch the roof?

The physics of an elevator involves the use of a motor, pulleys, and counterweights to move the elevator car up and down. When the elevator starts moving upwards, the force of the motor accelerates the car and everything inside it, including the person. This acceleration creates a sensation of weightlessness, allowing the person to feel as if they are floating upwards. As the elevator continues to move upwards, the person and everything else inside it are still accelerating, eventually reaching the roof.

2. Can a person really touch the roof of an elevator?

Yes, it is possible for a person to touch the roof of an elevator. However, this is only possible if the elevator is moving upwards at a high enough speed and if the person jumps or reaches up towards the roof. It is not possible to touch the roof if the elevator is moving downwards or if it is moving at a slow speed.

3. Will inertia play a role in allowing a person to touch the roof of an elevator?

Yes, inertia is a key factor in allowing a person to touch the roof of an elevator. Inertia is the resistance an object has to changes in its motion. When the elevator starts moving upwards, the person inside it also starts moving upwards due to inertia. As the elevator continues to accelerate upwards, the person's inertia causes them to keep moving upwards, allowing them to touch the roof.

4. Is it safe to touch the roof of an elevator?

No, it is not safe to touch the roof of an elevator. In most elevators, there is not enough space between the top of the elevator car and the roof for a person to safely touch it. Additionally, attempting to touch the roof of an elevator can be dangerous, especially if the elevator suddenly changes direction or stops unexpectedly.

5. Does the weight of the person affect their ability to touch the roof of an elevator?

Yes, the weight of the person can affect their ability to touch the roof of an elevator. The more mass a person has, the more inertia they will have, and the more force it will take for them to reach the roof. This means that a heavier person may have a harder time touching the roof of an elevator compared to a lighter person, all other factors being equal.

Similar threads

I Why don't we "fly up" in an accelerating elevator?
    • Mechanics
Replies
11
Views
2K
I Forces and gravitational time dilation
    • Special and General Relativity
Replies
11
Views
1K
Elevator physics. [very graphic]
    • Other Physics Topics
Replies
6
Views
2K
Simple Pendulum in Free Fall: Surprising Motion and Video Evidence
    • Introductory Physics Homework Help
Replies
7
Views
2K
Wind past a flat roof, without hitting the sidewall
    • Classical Physics
Replies
19
Views
4K
How Is Work Calculated on an Elevator Cab in Physics Problems?
    • Introductory Physics Homework Help
Replies
2
Views
3K
Impulse: Jumping before the elevator crashes
    • Introductory Physics Homework Help
Replies
4
Views
11K
Space Elevator: Physics Challenge
    • Introductory Physics Homework Help
Replies
16
Views
6K
B Need help explaining river-boat problems
    • Other Physics Topics
Replies
26
Views
5K
Conceptual Newton's Law's Questions - HS Freshman Physics
    • Introductory Physics Homework Help
Replies
2
Views
3K

Hot Threads

Recent Insights

Back
Top