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Flashcards in Lecture 3 Deck (33):
1

Which planets have rings?

Jupiter, Saturn, Uranus, Neptune

2

How are rings formed?

Tidal forces of a planet stretch objects that come in too close and break them apart

3

What is the Roche-Limit of a moon?

The point at which the moon will break apart in tidal forces

4

What is energy?

The ability of an object to do work, a scalar

5

What is work?

Force acting over a distance (Work = F*d)

6

What is power?

Energy / unit time

7

What is the equation for Kinetic Energy?

E=1/2mv^2

8

How is energy stored?

It is stored as potential energy whenever a force moves a particle through a field that the particle interacts with.

9

What is the equation for potential energy?

E=mgh

10

When does a cloud in space have more gravitational potential energy?

When it is very spread out.

11

In what kind of system is energy conserved?

In an isolated system

12

What does Noether's theorem state?

The laws of physics do not change over time (time invariance)

13

When is a spring more massive?

After you compress it because of the energy you put in

14

What kind of energy is light?

Radiative energy

15

What factor determines the intensity of light?

The amplitude of the photon

16

What factor determines the color of light?

The energy of the photon

17

What does a diffraction grating do?

Produces the same effect as a prism (e.g. on the bottom of a CD)

18

WHat are the four ways in which matter can react?

Transmission, absorption, emission, and reflection

19

What kinds of objects transmit light?

Transparent objects

20

What kinds of objects Emit light?

Example: lightbulb

21

What kinds of objects absorb light?

opaque objects

22

What kinds of objects reflect light?

Mirrors

23

What is a wave?

A disturbance / oscillation that travels through spacetime with no mass transfer but some energy transfer.

24

What is unique about cherenkov radiation?

That particles move faster in water than light does in water.

25

What is millimeter astronomy?

Astronomy based on lights of wavelengths of 1 to 3 millimeters

26

What is submillimeter astronomy?

Astronomy based on lights of wavelengths less than a millimeter long.

27

How can we predict what objects are composed of using light?

Light interacts in different ways with different objects. Thus by recording the light that comes through / bounces off an object, we can predict the substances that caused the light to do that.

28

What kind of charges produce an electric field?

Stationary charges

29

What kind of charges produce a magnetic field?

Moving charges

30

What do Maxwell's equations describe?

The properties and interactions of electric and magnetic fields.

31

What was the effect of Young's double-slit experiment?

Observed the wave-particle duality

32

On what does the photoelectric effect depend?

On frequency ALONE

33

What was Roemer's experiment?

He used the eclipses of Io, Jupiter's moon to calculate the speed of light, but was off due to inaccurate measurements.