A metal ball of mass 5 kg falls from a height of 490m. how much time it will take to reach the ground (g=9.8m/s square)​

initial velocity u=0m/s

height h =490 m

mass m=5kg

acceleration due to gravity g=9.8m/s²

we have

s =ut +1/2 at²

h=0×t+1/2×9.8×t²

490=9.8t²

t²=490/9.8

t²=50

t=√50=5√2=7sec approx

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