Answer:
The volume of the cylinder is 
Explanation:
Given that,
The height of the cylinder is 13 cm
Radius of the cylinder is 4 cm
We need to find the volume of the cylinder. The formula that is used to find the volume of a cylinder is given by :

So, the volume of the cylinder is 
Answer: UVA rays occupy the frequency range between 7.1 . 10¹⁴ and 9.4. 10¹⁴ Hz.
Explanation:
UV rays are simply electromagnetic waves, which wavelength is just below the visible spectrum (hance the name ultraviolet, meaning beyond violet).
As any elecromagnetic wave, propagates in the free space at the same speed that light does, i.e. 3.10⁸ m/s.
Also, we know that there exists a direct relationship between the wave speed, her wavelength (distance travelled by the wave during one cycle time) and the frequency (the inverse of the time needed to complete one cycle).
This relationship can be written as the following equation:
v = λ . f ⇒ f = v/λ
Replacing by the extreme wavelengths, we find the corrresponding limit frequencies as follows:
f₁ = 3.10⁸ m/s / 320 . 10⁻⁹ m ⇒ f₁ = 9.4 . 10¹⁴ Hz.
f₂ = 3.10⁸ m/s / 400 . 10⁻⁹ m ⇒ f₂ = 7.1 . 10¹⁴ Hz.
As we know that the pitch of sound is directly proportional to the frequency as the frequency increases the pitch of sound increases and wavelength decreases
so the correct option is B
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Explanation:
the electrostatic force is also known as the coulomb force or coulomb interaction. it's the attractive or repulsive force between two electrically charged object. like charges repel each other while unlike charges attract each other. coulomb's law is used to calculate the strength of the force between two charger .