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3 years ago

A coin dropped from the top of a precipice (cliff) takes 2.42 to hit the ground. How highis the precipice (cliff)? .

Physics

1 answer:

goldfiish [28.3K]3 years ago

4 0

Answer:

28.7 m.

Explanation:

Hello,

In this case, since the coin is dropped from the rest condition at which the initial velocity is 0 m/s, we can compute the height of the precipice via the following equation:

$y=y_0+v_0*t-\frac{1}{2}gt^2$

Whereas the final height is 0, the initial one is to be computed and the gravity is considered as 9.8 m/s², therefore the height turns out:

$y=y_0+v_0*t-\frac{1}{2}gt^2\\\\y_0=\frac{1}{2}gt^2=\frac{1}{2}*9.8m/s^2*(2.42s)^2 \\\\y_0=28.7m$

It means that the height of the cliff is 28.7 m.

Regards.

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