Answer: C
Explanation: Amplitude controls loudness, and frequency controls pitch. The more frequent the higher pitch.
Yes it is possible. Spectrum of emitted light depends upon the chemical composition of the source. and the way of its excitation. a clear example to us is that of sun.
Answer: 
The following vectors have been given: 
The angle between these two vectors can be found by:




Answer:
The velocity of mass 2m is 
Explanation:
From the question w are told that
The mass of the billiard ball A is =m
The initial speed of the billiard ball A =
=1 m/s
The mass of the billiard ball B is = 2 m
The initial speed of the billiard ball B = 0
Let the final speed of the billiard ball A = 
Let The finial speed of the billiard ball B = 
According to the law of conservation of Energy

Substituting values

Multiplying through by 

According to the law of conservation of Momentum

Substituting values

Multiplying through by 

making
subject of the equation 2

Substituting this into equation 1




Multiplying through by 


