Answer:
993.52 Hz
Explanation:
The frequency of sound emitted by the stationery train is 1057 Hz.
The car travels away from the train at 20.6 m/s.
The frequency the observer hears is given by the formula:

where v = velocity of sound = 343 m/s
vo = velocity of observer
f = frequency from source
This phenomenon is known as Doppler's effect.
Therefore:

The frequency heard by the observer is 993.52 Hz.
Answer: 80m
Explanation:
Distance of balloon to the ground is 3150m
Let the distance of Menin's pocket to the ground be x
Let the distance between Menin's pocket to the balloon be y
Hence, x=3150-y------1
Using the equation of motion,
V^2= U^s + 2gs--------2
U= initial speed is 0m/s
g is replaced with a since the acceleration is under gravity (g) and not straight line (a), hence g is taken as 10m/s
40m/s is contant since U (the coin is at rest is 0) hence V =40m/s
Slotting our values into equation 2
40^2= 0^2 + 2 * 10* (3150-y)
1600 = 0 + 63000 - 20y
1600 - 63000 = - 20y
-61400 = - 20y minus cancel out minus on both sides of the equation
61400 = 20y
Hence y = 61400/20
3070m
Hence, recall equation 1
x = 3150 - 3070
80m
I hope this solve the problem.
Answer: y = 40 + 21t
Explanation:
Apply the equation of distance covered.
d = vt + C
Where d is the distance covered
v = velocity , t = time
C = constant = initial distance covered
For the case above....
d = y
y(t) = vt + C
But y(0) =40 = C
C = 40ft
velocity v = 21 ft/s
Therefore, the equation of the altitude is given by;
y(t) = 21t +40
y = 40 + 21t
Https://www.google.com/search?q=Why+do+atoms+have+an+overall+neutral+charge%3F&oq=Why+do+atoms+have+...
Neutrons are no exception. So, if an atom<span> has equal numbers of electrons and protons, the </span>charges<span> cancel each other out and the </span>atom<span> has a </span>neutral charge<span>.
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Answer:
Copper's composition does not change as its shape changes, hence it is a physical feature.
Explanation: