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An airplane is flying with a velocity of 240 m/s at an angle of 30.0° with the horizontal, as the drawing shows. When the altitude of the plane is 2.4 km, a flare is released from the plane. The flare hits the target on the ground. What is the angle θ?

User Cyague
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Since the flare is released from the plane, it has the same initial velocity as the plane, i.e., 240 m/s at an angle of 30 degrees with the horizontal.

Let's assume that the distance from the plane to the target is d, and the altitude of the plane is h. The angle θ is the angle between the plane and the target.

Using trigonometry, we can write:

tan θ = h/d

We need to find the value of θ. To do that, we need to find the values of h and d.

We know that the altitude of the plane is 2.4 km = 2400 m. Let's call the time it takes for the flare to hit the target t. Since the flare is moving under gravity, its motion can be described as:

h = (1/2)gt^2

where g is the acceleration due to gravity, which is approximately 9.81 m/s^2.

The horizontal distance traveled by the flare in time t is:

d = vt

where v is the horizontal component of the velocity of the flare/plane, which is given by:

v = 240 cos 30° = 240 × √3/2 = 120√3 m/s

Equating the expressions for h and d, we get:

(1/2)gt^2 = vt

Solving for t, we get:

t = 2h/g = 2 × 2400/9.81 = 489.55 s

Substituting this value of t in the expression for d, we get:

d = vt = 120√3 × 489.55 ≈ 70000 m

Now we can find θ:

tan θ = h/d = 2400/70000 ≈ 0.0343

θ = tan^(-1)(0.0343) ≈ 1.96°

Therefore, the angle θ is 1.96 degrees.

User Rubendob
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