Answer: because ν = velocity/λ where ν and λ are the frequency and wavelegth of the wave.
Explanation: In order to explain this problem we have to consider the relationship between frequency and wavelengths which are related by the velocity of the wave as follows ν*λ=v where ν and λ are the frequency and wavelegth of the wave. These parameters have an inverse proportionality.
Then, ν = velocity/λ
Answer:
Most of us have experienced that pivotal peak of pain, anger or frustration in which we want to scream “I hate my life.” Yet, the feeling that a dark cloud has specifically settled over us and our experiences can feel pretty isolating. The truth is, no matter how singled out or overwhelmed we feel, and no matter what area we are struggling in, we are not alone. More than half of U.S. workers are unhappy with their job. One in 10 Americans struggles with depression. All of us have moments of utter despair. Escaping from this hopeless-seeming state may feel impossible. Yet, in reality, we are not doomed, and we are not powerless. No matter what our circumstances, we can all learn tools to help us emerge from the darkest moments in our lives.
A barometer is used to measure air pressure!
Answer:
B.) by interfering with sound waves
Explanation:
As we know that the interference of sound waves is of two types
1). constructive interference
2). destructive interference
now we know that constructive interference means the resultant intensity will be more than the intensity of interfering waves as here two waves are in same phase.
In destructive interference the resultant of two waves is given by the minimum resultant of the intensity as here the phase of two waves are opposite to each other.
So we will say that

here in case of noise cancelling headphones we know that the phase of noise is always made in opposite phase with the sound which is used to cancelled the noise.
This will reduce the noise and we will get a clear sound
Answer:
8.1 x 10^13 electrons passed through the accelerator over 1.8 hours.
Explanation:
The total charge accumulated in 1.8 hours will be:
Total Charge = I x t = (-2.0 nC/s)(1.8 hrs)(3600 s/ 1 hr)
Total Charge = - 12960 nC = - 12.96 x 10^(-6) C
Since, the charge on one electron is e = - 1.6 x 10^(-19) C
Therefore, no. of electrons will be:
No. of electrons = Total Charge/Charge on one electron
No. of electrons = [- 12.96 x 10^(-6) C]/[- 1.6 x 10^(-19) C]
<u>No. of electrons = 8.1 x 10^13 electrons</u>