Daniel Jee / Staff reporter
You’ve probably imagined at least once that the elevator suddenly stops working and falls to the ground. If this imagination really happens to you, what choice will you make?
Perhaps as a solution to the imagination, some people might have thought of jumping just before the elevator touches the ground and settling on it after the elevator absorbs the shock. But can that imagination actually make you survive?
To imagine the above, you have to assume several situations. First, when the elevator starts to fall, the inside becomes weightless and our body floats. Then you can’t jump, so you need to set the condition that your body is attached to the elevator and that all safety devices doesn’t work when the elevator falls.
The safety devices are emergency devices in case the elevator falls. Many people are worried about falling without knowing the existence of a safety devices, but if an elevator breaks down, the safety devices prevent the fall, so the probability of a fall is low.
But let’s say you’re in an elevator with a low probability that the safety devices don’t work. Of course, you don’t experience zero gravity when you fall.
If you set the falling height to 40 stories, you and your elevator fall from a height of about 120 meters.
According to Physics 11, the speed at which the elevator falls can be obtained using the formula that the kinetic energy and potential energy are same.
(1/2)(mass)(velocity)^2=(mass)(acceleration due to gravity)(height)
1/2mv^2 = mgh
v^2=2gh
v^2=2×9.8×120
v=48.49m/s
People can jump at an average speed of approximately 2.0 m/s, so if you jump, you can reduce your falling speed to 46.49m/s. (48.49 m/s-2.0 m/s = 46.49 m/s)
Human cannot survive in a falling elevator at 167.364 km/h (46.49 m/s).
Too high height? Then, let’s set it as the third floor.
The 3rd floor is about 9m.
If you use the same formula,
(omitted)
V=13.28m/s= 47.8km/h
You may survive, but it seems to hurt a lot.
But there is another factor to consider before that.
That’s reaction time.
(velocity)=(acceleration due to gravity)x(time)
V=gt
13.28=9.8t
T=1.36s
You have to recognize and respond to the situation in 1.36s. The human reaction speed is usually about 0.8s, so you may react, but if you can’t jump at the right time of hitting, you will crash your head into the ceiling of the elevator.
The situation in which an elevator falls is more hopeless than expected.
Then, how can you increase the chances of survival and minimize injuries?
First, there is a way to lie down on the elevator floor and wrap your face and head. It is intended to disperse the impact as much as possible with the ribs which are known to recover faster than other parts.
The best way is to lie down or to hold the handle well while slightly bowing your head in a horse riding position in the corner and protecting head. There is a shock-absorbing buffer on the bottom floor, so there will be less shock when you fall and hit the floor.
If the elevator breaks down, there is a risk of a real falling and crash, so it’s best not to touch other buttons or devices and wait calmly after calling for a rescue.
Sources:
Average jump time: 0.2s
Average jump height: 0.4m
Images: