## Problem 1B.3

Yazmin Bocanegra 3L
Posts: 51
Joined: Thu Jul 25, 2019 12:17 am

### Problem 1B.3

1B.3. From the following list of observations, select the one that best supports the idea that electromagnetic radiation has the properties of particles. Explain your reasoning.

b) electron diffraction
c) atomic spectra
d) the photoelectric effect

The photoelectric effect is correct, but I do not completely understand the reasoning as to why it is correct. Please send help and thank you!

andrewcj 2C
Posts: 102
Joined: Thu Jul 11, 2019 12:17 am

### Re: Problem 1B.3

Part of the experiment demonstrating the photoelectric effect revealed that more electrons can be ejected from metal by shining light on it if the wavelength of the light was increased. If light was viewed as a wave, we would expect increasing intensity to correlate to more electrons being ejected. However, this is not the case, which suggests light has particle-like properties.

Lauren Tanaka 1A
Posts: 109
Joined: Sat Aug 17, 2019 12:18 am

### Re: Problem 1B.3

The photoelectric effect is the correct answer because in that experiment they were able to find that there would be more electrons ejected from a piece of metal if the frequency of the light is increased. They tried to increase the intensity of the particular light source and the same amount or no electrons where ejected. They could then conclude that light had to be made up of particles.

Miriam Villarreal 1J
Posts: 105
Joined: Sat Aug 17, 2019 12:16 am

### Re: Problem 1B.3

Electromagnetic radiation has properties of particles because is characterized as being a form of light which is absorbed in discrete units (photons)

NRodgers_1C
Posts: 54
Joined: Thu Jul 25, 2019 12:15 am

### Re: Problem 1B.3

To confirm: the electrons are acting as the particles?

Also: Do short wavelengths always have high frequencies and long wavelengths always have low frequencies? Acknowledging the intensity of the light doesn't effect how many electrons are ejected, is it the length of the wavelength (short or long) or the degree of the frequency (high or low) that causes electrons to be ejected?