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emmainna [20.7K]
2 years ago
10

A football is kicked from ground level at an angle of 53 degrees. It reaches a maximum height of 7.8 meters before returning to

the ground. How long will the football spend in the air, in seconds?
Physics
1 answer:
Nonamiya [84]2 years ago
7 0

Answer:

1.61 second

Explanation:

Angle of projection, θ = 53°

maximum height, H = 7.8 m

Let T be the time taken by the ball to travel into air. It is called time of flight.

Let u be the velocity of projection.

The formula for maximum height is given by

H = \frac{u^{2}Sin^{2}\theta }{2g}

By substituting the values, we get

7.8= \frac{u^{2}Sin^{2}53 }{2\times 9.8}

u = 9.88 m/s

Use the formula for time of flight

T = \frac{2uSin\theta }{g}

T = \frac{2\times 9.88\times Sin53 }{9.8}

T = 1.61 second

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3 years ago
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2 years ago
When a board with a box on it is slowly tilted to larger and larger angle, common experience shows that the box will at some poi
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Answer:

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