A stone is thrown vertically upwards with an intinal velocity of 20 m/sec . find the maximum height it reaches and the time by it reachthe height (g=10 m/sec).

Maximum height is20m and time taken will be 2second

Explanation:

vi=20m/s

vf=0m/s

g=10m/s^2

Using third equation for objects falling freely

2gh=(vf)^2-(vi)^2

Putting values

2(10m/s^2)h=(0m/s)^2-(20m/s)^2

20h=400m

h=20m

Now we have to find the time

Using first equation of motion for objects falling down freely

vf=vi+at

substituting the equation

(vf-vi)/g=t

(0-20)/10=t

t=2second

the earths atmosphere is made up of nitrogen and oxygen. solids can turn into gasses through a process called sublimation. sublimation is the transition of a substance directly from the solid to the gas phase, without passing through the intermediate liquid phase.

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