Quiz 3

Question 1

State kepler’s third law of planetary motion

Answer 1

A planet’s orbital period (p) squared is equal to its average distance from the sun (a) cubed.

Question 2

Describe galileo’s major accomplishments in astronomy

Answer 2

Made the first astronomical measurements with the telescope. Showed that stars were much farther away than originally thought. Discovered sun spot and moon craters. Discovered moons around Jupiter and Venus phases.

Question 3

State 3 reasons against a heliocentric solar system

Answer 3

1. If earth were moving, falling and flying objects would be left behind.
2. Non-circular orbits contradicted the belief that the heavens were perfect and unchanging
3. Still no parallex measured

Question 4

Isaac newton’s major accomplishments related to astronomy

Answer 4

Laws of motion
Invented calculus
Law of gravity

Question 5

Kepler’s first law of planetary motion

Answer 5

The orbits of planets are ellipses with the sun as one focus

Question 6

State kepler’s second law of planetary motion. What does this mean with regard to the speed of the planet?

Answer 6

A planet swaps out equal areas in equal times. Moves fast when close to the sun and slow when far away.

Question 7

What is the value for the speed of light?

Answer 7

3 times 10 to the eighth meters per second

Question 8

What do the terms wavelength and frequency mean?

Answer 8

Wavelength is the distance from crest to crest. Frequency is how many Crests pass a point every second.

Question 9

How is the speed of light related to its frequency and its wavelength?

Answer 9

Frequency times wavelength equal speed

Question 10

List the types of electromagnetic waves from longest to shortest wavelength’s. Give a brief description of each type.

Answer 10

Radio waves are long wavelength low-frequency and low energy. Infrared light is heat. Visible light has a lambda of 400 nm violet and 700 nm red. Ultraviolet light is given off by the sun and absorbed by earths upper atmosphere. X-rays can penetrate human tissue. GammaRay’s are given off by radioactive nuclei. They have a short wavelength high frequency and high energy.

Question 11

Light behaves in two distinctly different ways. What are they?

Answer 11

Waves and particles

Question 12

How long does it take light to travel from the sun to the earth?

Answer 12

8 minutes and 20 seconds

Question 13

How long does it take light to travel from the earth to the moon?

Answer 13

1.3 seconds

Question 14

what is a photon?

Answer 14

Particle of light

Question 15

How can the energy of a photon be calculated?

Answer 15

Planck’s constant times speed of light divided by wavelength

Question 16

What do the variables in this equation represent?

Answer 16

E= energy
H= planck’s constant
C= speed of light
Lambda: wavelength

Question 17

Describe tycho brahe’s major accomplishments in astronomy

Answer 17

Made most accurate naked eye observations of the planets. Noticed a new start but was actually supernova.