SCI 103 Test 2

Question 1

luminousity

Answer 1

intrinsic brightness summed over this entire spectrum

Question 2

circumpolar star

Answer 2

any star or constellation closer to Polaris than the Big Dipper also moves in a circular path

Question 3

planetary nebula

Answer 3

the blown-off outer layers from ring-like structures

*core remains, outer parts are torn

Question 4

dead stars

Answer 4

stars that have used up their available nuclear fuels

Question 5

binary/companion stars

Answer 5

two stars - one has a smaller mass and smaller orbit while the other has a larger mass and a larger orbit
*both move with each other’s center of mass (which they move around)

Question 6

stellar magnitudes

Answer 6

brightest stars - 1st magnitude

dimmest star - 6th magnitue

Question 7

extra-terrestrial

Answer 7

things or events outside of Earth or its atmosphere

Question 8

wormholes

Answer 8

a hypothetical feature of space time that could be fundamentally a shortcut through space time
*If traversible wormholes exist, then they would allow time travel

Question 9

Einstein ring

Answer 9

when primary and secondary images within gravitational lensing are aligned

Question 10

gravitational lensing

aka cosmic telescope

Answer 10

phenomena resulting from the deflection of light in a gravitational field
-includes a telescope, deflector lens, primary and secondary images

Question 11

Magnification of images…

Answer 11

…depend on the alignment of the source, lens, and observers

Question 12

Light

Answer 12

electromagnetic radiation that can be seen with the eye

Question 13

light spectrum

Answer 13

high frequency/low wavelength
gamma rays
x-rays
UV
visible light
infrared
microwave
radio waves
low frequency/high wavelenth

Question 14

Reflection (two types)

Answer 14

specular - surface is smooth, returning rays will be parallel
diffuse - surface is rough, returning rays will not be parallel

Question 15

law of reflection

Answer 15

1: angle of incidence = angle of reflection
2: reflected ray lies in the same plane as the incidence ray and the normal to the surface at the point of incidence

Question 16

Generally (more/less) light is refracted than it is reflected

Answer 16

more!

Question 17

refraction

Answer 17

when the light moves from one medium to another

Question 18

refraction changes: wavelength, frequency, velocity

Answer 18

wavelength changes
frequency doesn’t change
velocity changes

Question 19

refractive index of medium

Answer 19

n=c/v
c-speed of light in vacuum
v-speed of light in medium

Question 20

law of refraction

Answer 20

1: sin(angle1)/sin(angle2) = n2/n1
2: incident ray, refracted ray, and normal lie in the SAME plane

Question 21

spectrum

Answer 21

an array of light arrange din order of wavelength
top-red
bottom-violet

Question 22

visible light spectrum

Answer 22

Red
Orange
Yellow
Green
Blue
Indigo
Violet
(upside down on full light spectrum-stars with V)

Question 23

Snell’s Law

Answer 23

sin(angle1)/sin(angle2) = n2/n1

Question 24

total internal reflection

*only possible when…

Answer 24

if the inside ray if above the critical angle it will be refracted into the same glass medium causing this
*possible ONLY IF n1>n2 (going from a more dense to a less dense medium)

Question 25

critical angle

Answer 25

when the angle coming from the one medium to another makes a ray of refraction that has a 90 degree angle with the normal

Question 26

real images

Answer 26

light rays pass through the image so that is appears on paper placed at the image

Question 27

virtual images

Answer 27

light rays do not actually pass through the image location so the image could not appear on paper

Question 28

In order to see you self image the minimum height of the mirror would have to be ____ of your height

Answer 28

half of your height!