Answer:
31.2 m/s
Explanation:
= Frequency of approach = 480 Hz
= Frequency of going away = 400 Hz
= Speed of sound in air = 343 m/s
= Speed of truck
Frequency of approach is given as
eq-1
Frequency of moving awayy is given as
eq-2
Dividing eq-1 by eq-2


= 31.2 m/s
The amount of diffraction depends on the wavelength of light, with shorter wavelengths being diffracted at a greater angle than longer ones (in effect, blue and violet<span> light are diffracted at a larger angle than is red light).
I hope my answer has come to your help. God bless and have a nice day ahead!
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Answer: 16.22 m/s^2
Explanation: g= GM/r^2 G= (6.67x 10^-11) M= 1.66(6x 10^24) r=(6400x 10^3) so
((6.67x10^-11)(1.66x 6x 10^24))/ (6400x10^3)^2 = 16.22 m/s^2
Acceleration is any change in speed or direction of motion.
The dimension of speed is [length/time],
so a change is [length/time²].
Popular units include [meter/second²] and [feet/second²] .
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Direction almost always boils down to an angle, (which technically
has no dimensions), so a change in direction is [angle/time] .
Popular units include [radian/second] and [degree/second] .
The average speed of the car for the entire trip can be calculate by using:

where S is the total distance covered by the car, and t is the total time taken.
The total distance travelled by the car is:

while the total time taken is:

so, the average speed of the car is:

so, the correct answer is (3) 85 km/h.