Answer:
V_{average} =
, V_{average} = 2 V
Explanation:
he average or effective voltage of a wave is the value of the wave in a period
V_average = ∫ V dt
in this case the given volage is a square wave that can be described by the function
V (t) = 
to substitute in the equation let us separate the into two pairs
V_average = 
V_average = 
V_{average} = 
we evaluate V₀ = 4 V
V_{average} = 4 / 2)
V_{average} = 2 V
From the given equation we can deduce what changes will occur if the frequency of the sound is doubled
V= f (λ)
Speed = frequency. Wavelength
When the frequency is doubled, speed will not change. Because speed depends on factors like temperature, air pressure, density of the gas. Since all these factors are unchanged thus speed will remain unchanged
Frequency is the number of waves produced per second. Frequency and wavelength are inversely proportional .Thus, if the frequency is doubled the wavelength would be halved.
Answer: 
Explanation:
The Compton Shift
in wavelength when the photons are scattered is given by the following equation:
(1)
Where:
is a constant whose value is given by
, being
the Planck constant,
the mass of the electron and
the speed of light in vacuum.
the angle between incident phhoton and the scatered photon.
We are told the maximum Compton shift in wavelength occurs when a photon isscattered through
:
(2)
(3)
Now, let's find the angle that will produce a fourth of this maximum value found in (3):
(4)
(5)
If we want
,
must be equal to 1:
(6)
Finding
:
Finally:
This is the scattering angle that will produce
Given :
The ball of a ballpoint pen is 0.5 mm in diameter and has an ASTM grain size of 12.
To Find :
How many grains are there in the ball?
Solution :
Volume of ball of the ballpoint is :

Now, grain size of 12 has about 520000 grains/mm³.
Therefore, number of grains are :
