<h3><u>Answer;</u></h3>
Expulsion of electrons with varying frequencies of light observed in the photoelectron effect.
<h3><u>Explanation</u>;</h3>
- <em><u>The photoelectric effect supports a particle theory of light in that it behaves like an elastic collision between two particles, the photon of light and the electron of the metal.</u></em>
- Albert Einstein observed the photoelectric effect in which ultraviolet light forces a surface to release electrons when the light hits. He explained the reaction by defining light as a stream of photons, or energy packets.
To solve this problem it is necessary to apply the law of Malus which describes the change in the Intensity of Light when it crosses a polarized surface.
Mathematically the expression is given as

Where,
= Initial Intensity
I = Final Intensity after pass through the polarizer
= Angle between the polarizer and the light
Since it is sought to reduce the intensity by half the relationship between the two intensities will be given as

Using the Malus Law we have,





Angle with respect to maximum is 
<span>To begin, the formula for finding frequency when wavelength is known is "f = c / w" when c is the constant velocity (3 * 10^8 m/s). To convert the wavelength into a common form (m/s), it will have to be multiplied by 10^-2. This leaves the equation as "f = 3.0 * 10^8 / (2.4 * 10^-5 * 10^-2), or 2.4 * 10^-7. This gives 1.25 * 10^15 m/s as the frequency.</span>
The average speed of the whole travel is equal to <u>400 mph</u>.
Why?
From the statement, we know that whole travel is divided into three parts. For the first part (traveling from New York to Chicago), we have that it was 3.25 hours and the covered distance was half of the total distance (1400mi). For the second part, we have that it was 1 hour (layover time), and the covered no distance. For the third part (traveling from Chicago to Los Angeles), we have that it was 2.75 hours, and it took the other half of the total distance (1400mi).
We can calculate the average speed of the whol travel using the following formula:

Now, substituting and calculating, we have:


Hence, we have the average speed of the whole travel is equal to 400 mph.
Have a nice day!