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Vladimir79 [104]

4 years ago

13

Fast Bullets A rifle with that shoots bullets at 420 m/s shoots a bullet at a target 49.8 m away. How high above the target must

the rifle barrel be pointed to ensure that the bullet will hit the target?

1 answer:

Nezavi [6.7K]4 years ago

8 0

Answer:

0.08°

Explanation:

velocity of projection, u = 420 m/s

Horizontal range, R = 49.8 m

Let the angle of projection is θ.

Use the formula for the horizontal range.

$R=\frac{u^{2}Sin2\theta }{g}$

$49.8=\frac{420^{2}Sin2\theta }{9.8}$

Sin 2θ = .0027

2θ = 0.1585

θ = 0.08°

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