Author: Justin Jones

1. Solve for the total force on the negative charge below.  At what angle respect to the x-axis does the negative particle travel?

2. In terms of units, prove that the equation below is equal to a Joule per Coulomb. (Hint: What is a Joule equivalent to?)

Assume charge 1 = charge 2 = 6 x 10^-6 C and charge 3 = -8 x 10^-6 C

If distance 1 = 1.5 cm and distance 2 = 1 cm, then what is the total force and direction on each charge?

1. Assume the distance between an object and a convex lens is 0.72 m. If the distance between the lens and the image is 0.38 m, then what is the focal point? Sketch the the ray diagram. Answer: 0.25 m

2. Assume the frequency of a light wave is 8 x 10^14 Hz traveling at the speed of light. The length between the barrier and the screen is 0.28 m while the distance between the double slits is 1.9 x 10^-6 m. What is the distance between the two diffraction points? Answer: 0.06 m

3. A ray of light traveling from air into glass strikes the surface at an angle of 24 degrees. Assume the index of refraction for the air is 1 and 1.57 for the glass. What is the angle of refraction? Answer: 15 degrees

4. Assume the angle of incidence is 49 degrees while the angle of refraction is 28 degrees. If the light beam is traveling from air to an unknown medium, what percentage of the speed of light does the light beam travel in the second medium? Answer: 62 %

1. Sketch and explain the difference between convex and concave mirrors.
2. Sketch and explain the difference between convex and concave lenses.
3. How causes refraction of sound air?
4. What happens when light refracts in water or glass?
5. Explain the difference between refraction and reflection.

#2

Click Here: Light & Color Questions

# 3 List at least one application of each wave on the EM spectrum in the correct order.

#4 Explain how a polarizer works and research some applications. In other words, how are they used?

Answer in at least two complete sentences:
1. How does light behave like a wave?
2. How does light behave like a particle?

#3 If the wavelength of an EM wave is 600 nanometers, then what is the frequency? Assume the wave is traveling through glass.

#4 Use the link below to summarize how a shadow can move faster than the speed of light.

https://thescienceexplorer.com/universe/4-ways-travel-faster-speed-light

#1 Describe the observation of the photoelectric effect.
#2 How many photons does it take to eject an electron? Explain.

1. Assume the sound  pressure level of a source is 50 decibels. What is the pressure of the sound wave in Pascals? 100 decibels?
2. Explain how an opera singer can shatter glass.
3. According to the Doppler Effect, prove that addition applies to a receding sound source. Plug in your own values for velocity and frequency of the source.

(YOU MAY COMPLETE CORRECTIONS FOR TODAY’S RETURNED HOMEWORK)

1. Prove that an unknown sound source with a pressure of  0.05 Pa has a lower SPL than 100 dB. Give an example of the unknown sound source.
2.  Prove that the reference sound pressure is equal to zero decibels.
3. In terms of compressions and rarefactions, what happens when there is an increase in SPL?
4. By how much does SPL increase/decrease when the wavelength is doubled? Explain.
5. What is the velocity of a sound wave at 68 degrees Fahrenheit? 69 degrees Fahrenheit?