When visible light, X rays, gamma rays, or other forms of electromagnetic radiation are shined on certain kinds of matter, electrons are ejected. That phenomenon is known as the photoelectric effect. The photoelectric effect was discovered by German physicist Heinrich Hertz (1857–1894) in 1887. You can imagine the effect as follows: Suppose that a metal plate is attached by two wires to a galvanometer. (A galvanometer is an instrument for measuring the flow of electric current.) If light of the correct color is shined on the metal plate, the galvanometer may register a current. That reading indicates that electrons have been ejected from the metal plate. Those electrons then flow through the external wires and the galvanometer. HOPE THIS HELPED
First we find the energy level with the following formula, where a is the energy level, n1 is the final energy level, n2 is the starting energy level and r is Rydberg's constant in Joules

We insert the values


The wavelength is found with this formula, where h is Planck's constant and c is the speed of light

Finally we insert the values

Which is the same as 93.8 nm
Answer:
<h2>
44 m/s</h2>
Explanation:
In this problem we are expected to calculate the velocity of Georges movements.
Given data
Total distance covered by George= 850+250= 1100 meters
Time taken by George to cover the total distance= 25 seconds
We know that velocity is, v= distance/ time
Therefore substituting our data into the expression for velocity we have
v= 1100/ 25= 44 m/s
Hence the velocity in m/s is 44
Answer:
A) E = 4.96 x 10³ eV
B) E = 4.19 x 10⁴ eV
C) E = 3.73 x 10⁹ eV
Explanation:
A)
For photon energy is given as:


where,
E = energy of photon = ?
h = 6.625 x 10⁻³⁴ J.s
λ = wavelength = 0.25 nm = 0.25 x 10⁻⁹ m
Therefore,

<u>E = 4.96 x 10³ eV</u>
<u></u>
B)
The energy of a particle at rest is given as:

where,
E = Energy of electron = ?
m₀ = rest mass of electron = 9.1 x 10⁻³¹ kg
c = speed of light = 3 x 10⁸ m/s
Therefore,


<u>E = 4.19 x 10⁴ eV</u>
<u></u>
C)
The energy of a particle at rest is given as:

where,
E = Energy of alpha particle = ?
m₀ = rest mass of alpha particle = 6.64 x 10⁻²⁷ kg
c = speed of light = 3 x 10⁸ m/s
Therefore,


<u>E = 3.73 x 10⁹ eV</u>