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1.3.1)

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Given data :

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Fired angle θ = 20°

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Initial velocity v₀ =  250 m/s

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Earth gravity g = 9.8 m/s

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The time for the bullet to reach the maximum height t_max = ?

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Formula :

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Maximum time t_max = (v₀sinθ)/g

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Substitute : v₀ =  250 m/s , θ = 20° and  g = 9.8 m/s.

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t_max = (250sin20) / (9.8)

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t_max = (250×0.342) / (9.8)

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t_max = 8.72 sec

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The time for the bullet to reach the maximum height :  t_max = 8.72 sec

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