The stretching out of time due to motion is called time.....?

YIKES. its Dilation

The stretching out of time due to motion is called time dilation. It is a phenomenon predicted by Einstein's theory of relativity. Time dilation occurs when an object or observer is moving relative to another object or observer. As an object's velocity increases, time appears to pass more slowly for that object compared to a stationary observer.

To understand time dilation, you need some basic knowledge of special relativity. The equation to calculate time dilation is:

t' = t * √(1 - v^2/c^2)

Where:
t' is the dilated time experienced by the moving object or observer.
t is the proper time experienced by a stationary observer.
v is the relative velocity between the two objects.
c is the speed of light in a vacuum.

So, to calculate time dilation, you need to know the relative velocity between the objects and the value of the speed of light. By plugging in these values into the equation, you can determine the dilation of time.

It's worth noting that time dilation is a significant factor at speeds close to the speed of light. It has been observed in various experiments and is crucial in understanding many aspects of modern physics, such as space travel and GPS systems.