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An Airplane diving at an angle of 37° with the horizontal drops a mail bag at an altitude of 730m. The projectile hits the ground 5 sec. after being released. What is the speed of the air craft?

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Final answer:

The speed of the aircraft is 300 m/s.

Step-by-step explanation:

First, we need to find the time of flight by using the vertical motion equation:

h = ut + (1/2)gt^2

Where h is the altitude, u is the initial vertical velocity, g is the acceleration due to gravity, and t is the time.

Plugging in the given values: h = 730m, u = 0 m/s (as the mail bag is dropped vertically), and g = 9.8 m/s^2:

730 = 0 + (1/2) * 9.8 * t^2

Simplifying the equation, we get:

t^2 = (2 * 730) / 9.8

t^2 = 148.98

t = sqrt(148.98)

t = 12.2s

Next, we can find the horizontal displacement (x) using the horizontal motion equation:

x = vt

Where v is the horizontal velocity and t is the time of flight.

Plugging in the given values: x = v * 12.2

And knowing that the angle of descent is 37° and the vertical velocity (v) can be found using trigonometry:

v = 300 * cos(37°)

Plugging in the value of v:

x = 300 * cos(37°) * 12.2

Finally, we can calculate the speed of the aircraft using the formula:

speed = sqrt(v^2 + u^2)

Substituting the values: speed = sqrt((300*sin(37°))^2 + (300*cos(37°))^2)

Simplifying this equation: speed = sqrt(300^2 * (sin^2(37°) + cos^2(37°)))

Since sin^2(37°) + cos^2(37°) = 1, the equation simplifies to: speed = sqrt(300^2) = 300 m/s

User Peter Staranchuk
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