a jet passes overhead at an altitude of 500m. when the plane is directly overhead, the sound of its engine appears to come from a point at the same altitude but 500tan(22degrees) away. [[[They give a figure in which the sound at point A, the airplane, and the observer at ground level form a right triang.e with the vertex at which the observer stands is a 22 degree angle]]] If the average temperature of the air is 10.0 degrees C, how fast is the plane moving?
ok so i figured out that the speed of sound in air is 337m/s, but how do I calculate the plane's velocity?
2007-02-10 08:25:08 · 1 answers · asked by tmrrwtdy 1 in Science & Mathematics ➔ Physics
In the time it takes the sound to reach the ground the plane will have moved a distance = v*t
Since the speed of light is so much faster, assume that the light travels instantaneoulsy to the ground.
Time it takes the sound to travel to the ground
500=337*t
t=500/337
t=1.48 seconds
In that time the plane moved to a distance that is
500*tan(22)
which is equal to v*t
v=500*tan(22)/1.48
=136 m/s
Note that
v=337*tan(22)
J
2007-02-10 08:38:41 · answer #1 · answered by odu83 7 · 0⤊ 0⤋