A car falls off a ledge and drops to the ground in `0.5 s`. let` g=10 m//s^(2)` (for simplifyng the calculation).
(i) what is its speed on striking the ground ?

what is its average speed during 0.5s?
(iii) How high is the ledge from the ground ?

Answer

(i) `5m//s` (ii)` 2.5 m//s` (iii)`1.25m`

Explanation

Here, `u = 0, t = 0.5 s, g = 10 m//s^(2)`
(i) `v = u +g t = 0 +10 xx 0.5 = 5 m//s` (ii) Average spped `=(u +v)/(2) = (0+5)/(2) = 2/5 m//s`
(iii) From `h = ut +(1)/(2) g t^(2), h = 0+(1)/(2) xx 10(0.5)^(2) = 1.25m`