Answer:
Explanation:
Rydberg formula is used to calculate the wavelengths of the spectral lines of many chemical elements. For the hydrogen, is defined as:
Where 
is the Rydberg constant for hydrogen and 
, 
are the lower energy state and the higher energy state, respectively.
atoms of lithium, sodium,
and potassium almost never found alone in nature because t<span>hey have only one electron in their outer most
shell which makes them very reactive and they react with other atoms thats why.
I hope this can help you</span>
<h2>
Answer:</h2>
<u>A. A nuclear power plant</u> produces radioactive wave.
<h2>
Explanation:</h2>
A plant in which a nuclear reactor is used as a source to produce heat is known as nuclear power plant. The heat formed by the reactor is used to form steam which can be used to drive turbines to produce electricity.
The coolant in reactor gets heated by the fission process taking place in the reactor. It is a cyclic process where the steam is condensed and reverted back. A nuclear power plant in active condition produce a small amount of radiation which can be sensed within a radius of 50 miles.
Answer:
The speed of the electron is 1.371 x 10⁶ m/s.
Explanation:
Given;
wavelength of the ultraviolet light beam, λ = 130 nm = 130 x 10⁻⁹ m
the work function of the molybdenum surface, W₀ = 4.2 eV = 6.728 x 10⁻¹⁹ J
The energy of the incident light is given by;
E = hf
where;
h is Planck's constant = 6.626 x 10⁻³⁴ J/s
f = c / λ
Photo electric effect equation is given by;
E = W₀ + K.E
Where;
K.E is the kinetic energy of the emitted electron
K.E = E - W₀
K.E = 15.291 x 10⁻¹⁹ J - 6.728 x 10⁻¹⁹ J
K.E = 8.563 x 10⁻¹⁹ J
Kinetic energy of the emitted electron is given by;
K.E = ¹/₂mv²
where;
m is mass of the electron = 9.11 x 10⁻³¹ kg
v is the speed of the electron
Therefore, the speed of the electron is 1.371 x 10⁶ m/s.
