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gregori [183]
3 years ago
9

A physics book is thrown horizontally at a velocity of 5.0 m/s from the top of a cliff 78.4 m high. How long does the book take

to reach the bottom of the cliff .
Physics
1 answer:
xenn [34]3 years ago
3 0

The book's vertical position in the air is

y=78.4\,\mathrm m-\dfrac12gt^2

where g=9.80\,\frac{\mathrm m}{\mathrm s}. It reaches the ground when y=0, at a time t such that

0=78.4\,\mathrm m-\dfrac12gt^2\implies t=4.00\,\mathrm s

So it takes the book 4 seconds to reach the bottom. The given initial velocity is irrelevant since it only has a horizontal component; vertically, the book is starting from rest.

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Lyrx [107]

Answer:

THE RUBBER BALL

Explanation:

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      The final speed at which it bounces bank v  - 3 \ m/s

      The mass of the clay ball  is  m_c =  2  \ kg

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       The final speed of the clay ball is  v = 0 \  m/s

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       I  =  \Delta p

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For the clay ball

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8 0
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Explanation:  

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6 0
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