Due to the way terminal velocity caps the maximum speed that something can fall, a small and light object like a penny will never gain enough speed to kill someone regardless of how high it is dropped from.
Physics is a natural science concerned with the study of matter and it’s relation to space and time. It looks at concepts related to this like energy and force in order to understand the behaviors of the universe.
The one-electron universe theory postulates that all electrons and positrons are actually a single entity moving back and forth in time.
In theory, the speed of light, in a perfect vacuum, measured from an inertial frame, is constant with an exact value of 299,792,458 m/s.
There is no limit to the amount of times one can fold a piece of paper in half if the paper is large enough. However, because the thickness of the paper grows exponentially, a lot of paper would be needed to make more than 8 folds.
The bed of nails principle states that while laying on one nail is enough to puncture a person’s skin, laying on many distributed nails isn’t.