Answer:

Explanation:
c = Speed of wave
= Density of medium
A = Area
= Frequency

Intensity of sound is given by

So,

We get

The ratio is 
Earth's gravity and the satellite's velocity keeps it so that it stays in orbit. (there is a more complicated side, too...)
Answer:
So coefficient of kinetic friction will be equal to 0.4081
Explanation:
We have given mass of the block m = 0.5 kg
The spring is compressed by length x = 0.2 m
Spring constant of the sprig k = 100 N/m
Blocks moves a horizontal distance of s = 1 m
Work done in stretching the spring is equal to 
This energy will be equal to kinetic energy of the block
And this kinetic energy must be equal to work done by the frictional force
So 


So coefficient of kinetic friction will be equal to 0.4081
Answer:
the Arrow X shows the direction of amplitude
Explanation:
As the amplitude is the maximum displacement of a wave from the mean position
Have wavelengths that are longer than normal.