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a boy throw a ball upward from the top of a cliff 73m high.Calculate the time in which ball will fall on the ground and the velocity of ball at that time

User Janis F
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1 Answer

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The ball rises for v/g seconds; which equals 14.7/9.8=1.5 seconds . After this time, it’s height will be:


h(t)=g/2(1.5)²+14.7(1.5)


=-4.9 x 2.25 + 22.05


=11.025m


The ball then falls for 49+11.025=60.025m, which takes:


g/2t²=60.025


t²=12.25


t=3.5 secs


Total time: 1.5+3.5=5 seconds

User MrFusion
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