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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?

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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Answer:

Part a)

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Now the total displacement of the train is given as

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$d = 5.3\hat i + 12.8 \hat j$

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$T = 1.83 h$

now average velocity is given as

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$v_{avg} = 2.89\hat i + 6.99\hat j$

Part a)

magnitude of the average velocity is given as

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Part b)

Direction of the velocity is given as

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$tan\theta = \frac{6.99}{2.89}$

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