Traditional Culture Encyclopedia - Photography major - When someone takes a picture indoors with the window as the background, he only takes a small stone falling freely from the window in the picture. The exposure time of this photo is known.

When someone takes a picture indoors with the window as the background, he only takes a small stone falling freely from the window in the picture. The exposure time of this photo is known.

Located within 0.02s of exposure, the actual falling distance of the stone is L. According to the meaning of the question:

4 cm: 100 cm = 1.6 cm: length

Solution: l = 40 cm = 0.4 m.

It can be calculated that the instantaneous speed at the beginning of stone intake is:

V = lt = 0.40.02 = 20m/s.

If the falling rock is a free fall, then: v ′ 2 = 2gh.

Solution: h = 40020 = 20m.

A: The stone fell about 20 meters from the edge of the window.