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Describe free fall.

Describe free fall.

Answers

sharon
A body falling freely in a vacuum starts from an initial velocity zero and accelerates at approximately 9.8ms-2 towards the centre of the earth. This is called the acceleration due to gravity g. In this case, the air resistance is assumed to be negligible. Note that in a vacuum, a feather and a stone released from the same height will take the same amount of time to reach the surface of the earth.
Therefore, in the three equations of linear motion u=0m/s, s=h and a=g. thus the three equations become:
v=gt, (from v=u+at)
h=½gt2, (from s=ut+½gt2)
v2=2gh, (from v2=u2+2as)
From the above equations:
- v= (2gh)½, where v is the velocity of the body just before it hits the ground.
- h=½gt2=v2/2g, where h is the height through which the body falls.
- t=v/g=(2h/g)½, where t is the time of flight.
sharon kalunda answered the question on April 24, 2019 at 05:44

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