Speed of light and distance to Sun If the speed of light is 300,000 km/sec, and it takes light 8 minutes to reach Earth from the sun, how far is the Earth from the sun? million kilometers million meters 3. 40,000 km 4. 40,000 meters million kilometers million meters

Speed of light and distance to Sun If the speed of light is 300,000 km/sec, and it takes light 8 minutes to reach Earth from the sun, how far is the Earth from the sun? million kilometers million meters 3. 40,000 km 4. 40,000 meters million kilometers million meters

Eclipses of Jupiter's moon In class I demonstrated why an observer that did not move relative to Jupiter would find that the time they measure between an eclipse of one of Jupiter's moons is different from someone who is moving either toward or away from Jupiter. If an observer is moving toward Jupiter, will they find that the time between eclipses is more or less than someone who is moving away from Jupiter? –More –Less

Eclipses of Jupiter's moon In class I demonstrated why an observer that did not move relative to Jupiter would find that the time they measure between an eclipse of one of Jupiter's moons is different from someone who is moving either toward or away from Jupiter. If an observer is moving toward Jupiter, will they find that the time between eclipses is more or less than someone who is moving away from Jupiter? –More –Less

Light bending Which color light will bend more when passed through a prism? 1. Green 2. Razzmatazz 3. Violet 4. Yellow 5. Lemon chiffon 6. Chartreuse

Light bending Which color light will bend more when passed through a prism? 1. Green 2. Razzmatazz (redish) 3. Violet 4. Yellow 5. Lemon chiffon (yellowish) 6. Chartreuse (yellow-green)

Overlapping waves In the top panel of the figure, two waves on a rope are shown to be approaching each other. At some instant in time, the waves overlap. Which of the following images best represents the state of the rope when the two waves overlap?

t=1 t=2

What is top + bottom? t=3 Amplitude of bottom wave is equal to that of top wave A A

What is top + bottom? t=3 At blue, amplitude of top wave is higher than bottom (by about A/2) At red, amplitude of top wave is equal and opposite amplitude of bottom A A

What is top + bottom? t=3 At blue, amplitude of top wave is higher than bottom (by about A/2) At red, amplitude of top wave is equal and opposite amplitude of bottom

Overlapping waves In the top panel of the figure, two waves on a rope are shown to be approaching each other. At some instant in time, the waves overlap. Which of the following images best represents the state of the rope when the two waves overlap?

Spectrum There are dark lines in the absorption spectrum that represent missing light. What happened to this light that is missing in the absorption line spectrum? 1. This light was converted to radio waves. 2. This light was converted to gamma rays. 3. This light was converted into an atom. 4. This light was absorbed by an atom in the gas and then scattered in a random direction.

Spectrum There are dark lines in the absorption spectrum that represent missing light. What happened to this light that is missing in the absorption line spectrum? 1. This light was converted to radio waves. 2. This light was converted to gamma rays. 3. This light was converted into an atom. 4. This light was absorbed by an atom in the gas and then scattered in a random direction.

Spectrum 2 Imagine that your are looking at two different spectra of the Sun. Spectrum #1 is obtained using a telescope that is above Earth’s atmosphere (for example, on the Moon). Spectrum #2 is obtained using a telescope located on the surface of Earth. Which spectrum is Spectrum #2 and why. Select the best answer.

Spectrum 2 Imagine that your are looking at two different spectra of the Sun. Spectrum #1 is obtained using a telescope that is above Earth’s atmosphere (for example, on the Moon). Spectrum #2 is obtained using a telescope located on the surface of Earth. Which spectrum is Spectrum #2 and why. Select the best answer.

Electromagnetic radiation energy The equation that tells us how much energy electromagnetic radiation has is E = hc/, where is the wavelength. According to this formula, which of the following will have the most energy? 1. A red photon 2. A green photon 3. A violet photon 4. A yellow photon 5. All are the same

Electromagnetic radiation energy The equation that tells us how much energy electromagnetic radiation has is E = hc/, where is the wavelength. According to this formula, which of the following will have the most energy? 1. A red photon 2. A green photon 3. A violet photon 4. A yellow photon 5. All are the same

Electromagnetic radiation speed Which of the following forms of electromagnetic radiation has the highest speed in empty space? (A) A violet photon (B) A green photon (C) A red photon (D) A yellow photon (E) All are the same

Electromagnetic radiation speed Which of the following forms of electromagnetic radiation has the highest speed in empty space? (A) A violet photon (B) A green photon (C) A red photon (D) A yellow photon (E) All are the same (and equal to c) Applies to all electromagnetic waves!

Photons and Electromagnetic Radiation What is the difference between light and electromagnetic radiation? 1. A light photon travels faster 2. They are the same thing. What we call visible light is electromagnetic radiation with a frequency that our eyes can detect. 3. A light photon travels slower 4. Electromagnetic radiation can interact with electromagnets while light cannot

Photons and Electromagnetic Radiation What is the difference between light and electromagnetic radiation? 1. A light photon travels faster 2. They are the same thing. What we call visible light is electromagnetic radiation with a frequency that our eyes can detect. 3. A light photon travels slower 4. Electromagnetic radiation can interact with electromagnets while light cannot

Rutherford's atom Rutherford shot alpha particles at a thin foil and was able to show that 1. Gold foil has no neutrons 2. Gold foil has no electrons 3. The atom is generally very empty except for a dense area where protons and neutrons are concentrated. 4. The atom is generally very uniform and when you shoot an alpha particle at it, it is very likely to hit a proton an be reflected back.

Rutherford's atom Rutherford shot alpha particles at a thin foil and was able to show that 1. Gold foil has no neutrons 2. Gold foil has no electrons 3. The atom is generally very empty except for a dense area where protons and neutrons are concentrated. 4. The atom is generally very uniform and when you shoot an alpha particle at it, it is very likely to hit a proton an be reflected back.