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2 years ago

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A jet fighter pilot wishes to accelerate from rest at 5 ggg to reach Mach-3 (three times the speed of sound) as quickly as possi

ble. Experimental tests reveal that he will black out if this acceleration lasts for more than 5.2 ss . Use 331 m/sm/s for the speed of sound

1 answer:

ad-work [718]2 years ago

7 0

Answer

given,

acceleration, a = 5 g = 5 x 9.8 = 49 m/s²

speed of sound, v = 331 m/s

speed , v = 3 Mach = 3 x 331 m/s = 993 m/s

time, t = 5.2 s

a) Calculating the time period of black out.

time required by the aircraft to black out

using equation of motion

v = u + a t

initial velocity = 0 m/s

993 = 0 + 49 t

t = 20.26 s

the required time to reach 3 Mach speed is more than the given time hence, pilot will black out.

b) now, calculating the maximum speed it can reach in 5.2 s

using equation of motion

v = u + a t

initial velocity = 0 m/s

v = 0 + 49 x 5.2

v = 254.8 m/s

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<h2>a) </h2>

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We know that they are linearly independent, cause to have one, and only one, plane through points P Q and R, this points must be linearly independent (as the dimension of a plane subspace is 3).

If they weren't linearly independent, we will obtain vector zero as the result of the cross product.

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