A freely falling body, falling from a height of 2km, and assuming g = 10m/s2, will strike the ground in a time of
- 40s.
- 80s.
- 20s.
Explanation from PART66Online
For a body falling from rest the distance is s = (1/2)g t^2. Rearranging, t = the square root of (2s / g) = the square root of (2 x 2000 / 10) = the square root of 400 = 20 seconds. The 40 s and 80 s figures are simply double and four times the correct time.
Asuka16 asked · 26 Nov 2012
Can you give me the formula for this?
Community Comments (2)
Assuming from rest(at 2km), ut is remove, so s=½at²
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