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3 years ago

The average velocity of a tennis ball is measured during serving and found to be 216 km/hr.

Physics

1 answer:

icang [17]3 years ago

7 0

Answer:

The time between hitting the ball and meeting the ground is $t=0.33\: s$

Explanation:

We have a semi parabolic motion here. We know that the initial speed 216 km/h or 60 m/s in the x-direction.

So we can use the following equation:

$v=\frac{\Delta x}{\Delta t}$

$60=\frac{20}{t}$

$t=\frac{20}{60}$

$t=0.33\: s$

hope it helps you!

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3 years ago

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storchak [24]

<span>On what:

f (is the focal length of the lens) = ?
p (is the distance from the object to the lens) =15.8 cm
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</span><span>Using the Gaussian equation, to know where the object is situated (distance from the point).
</span>
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$\boxed{\boxed{f = 3.318\:cm}}\end{array}}\qquad\quad\checkmark$

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4 years ago

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