Lets use an ambulance as an example:
Lets say we are stationary on a sidewalk and a ambulance is coming towards us, at first we hear the sound at a lower pitch as it is further away, but as the ambulance travels towards us the frequency, which denotes how many waves pass a given point per unit time (we are the point), will get higher, meaning an increase in pitch as the waves become "denser" or more compressed. As the ambulance travels away you will hear the sound at a lower pitch because the frequency of sound waves passing you per unit time is less and it will continue to lessen until the ambulance can no longer be heard.
Essentially--> higher frequency means higher pitch
The waves become more compressed as a it moves with velocity v towards a certain point.
Answer:
The object fell from about 38.14 meters
Explanation:
We can use the formula for displacement under accelerated motion due to gravity to find the velocity of the object had 30 m before hitting the ground :
![y_f-y_i=v_i * \,t-\frac{9.8}{2} \,t^2\\0-30=v_i \,(1.5)-4.9\,(1.5)^2\\-18.975=v_i\,(1.5)\\v_i=-12.65\,\,\frac{m}{s}](https://tex.z-dn.net/?f=y_f-y_i%3Dv_i%20%2A%20%5C%2Ct-%5Cfrac%7B9.8%7D%7B2%7D%20%5C%2Ct%5E2%5C%5C0-30%3Dv_i%20%5C%2C%281.5%29-4.9%5C%2C%281.5%29%5E2%5C%5C-18.975%3Dv_i%5C%2C%281.5%29%5C%5Cv_i%3D-12.65%5C%2C%5C%2C%5Cfrac%7Bm%7D%7Bs%7D)
Now, knowing this velocity, we can find the time it took to fall from the initial position to 30 m before hitting the ground:
![v_f=v_i-g\,*\,t\\-12.65=0-g \,*\,t\\t=\frac{12.65}{g} \\t\approx1.29\,\,s](https://tex.z-dn.net/?f=v_f%3Dv_i-g%5C%2C%2A%5C%2Ct%5C%5C-12.65%3D0-g%20%5C%2C%2A%5C%2Ct%5C%5Ct%3D%5Cfrac%7B12.65%7D%7Bg%7D%20%5C%5Ct%5Capprox1.29%5C%2C%5C%2Cs)
And now we can find what is the total distance covered in 1.5 s plus 1.29 seconds for this free falling object:
![y_f-y_i=v_i * \,t-\frac{9.8}{2} \,t^2\\0-y_i=0-\frac{9.8}{2} \,(2.79)^2\\-y_i=-38.14\\y_i=38.14\,\,m](https://tex.z-dn.net/?f=y_f-y_i%3Dv_i%20%2A%20%5C%2Ct-%5Cfrac%7B9.8%7D%7B2%7D%20%5C%2Ct%5E2%5C%5C0-y_i%3D0-%5Cfrac%7B9.8%7D%7B2%7D%20%5C%2C%282.79%29%5E2%5C%5C-y_i%3D-38.14%5C%5Cy_i%3D38.14%5C%2C%5C%2Cm)
The answer would be C. The gravitational force between two bodies however it is too small that it is overshadowed by that of earth. Gravitational force is the weakest force of all. Each body with a mass exerts a gravitational force onto each other but this value is so small that it can be neglected.
Neither analog nor digital
I think it causes physical weathering