Midterm

Question 1

You are at a latitude of 40 degrees North. The circumpolar region would be

Answer 1

50 degrees North to 90 degrees North

Question 2

With the planetarium, we found that the Sun took how long to return to the meridian (noon to noon)?

Answer 2

24 hours

Question 3

The star Vega sets at 9:00 pm on some night. A day later, Vega will set at:

Answer 3

8:56 pm

Question 4

Which of the following properly expresses the number 12,200,000,000 in scientific notation?

Answer 4

1.22 x 10^11

Question 5

It’s 2022 AD. I want to view what is going on in the year 1066 AD somewhere in the universe. I could:

Answer 5

Find a star that is 956 light years away and point a telescope at it

Question 6

After a series of observations are made, we construct a possible conclusion that describes our system. In order for this to be branded a “hypothesis,” our conclusion must:

Answer 6

provide testable predictions

Question 7

As you lie in bed, you realize from past experiences that you seem to get sick every time the temperature drops below 30 degrees. According to the scientific method this would be classified as:

Answer 7

forming a hypothesis

Question 8

A commercial advertising a diet pill says it is proven to help you lose weight. It has been recommended by a doctor who observed that some of his patients lost weight after taking the pill for a week

Why might we consider this claim to be pseudoscience?

Answer 8

no suggestion of how the pill was tested in a controled environment are provided

Question 9

A study of 40 undergraduates revealed that when the mind is relaxed and confident, anxieties which were previously focusing on other cognitive function, became ‘available for other tasks and processes.’ The students were split into two groups and both groups took identical multiple choice exams on a computer screen. One group was told the answer would flash quickly on the screen before each question. They were told that this happened too quickly for them to process the information, but were assured that it would register in their brains. This group was found to perform better on the exam even though they were actually at no advantage. In thinking about this experiment, we can say:

Answer 9

the placebo effect is primarily responsible as feeling better about taking the exam led to relaxation and higher scores

Question 10

Which of the following correctly describes the utility of Fermi problems?

Answer 10

we can take our experiential knowledge and make reasonable estimates for seemingly complex but important quantities

Question 11

The point in the sky above a local observer’s head at any given time is called the

Answer 11

zenith

Question 12

The Celestial Sphere turns once every day because

Answer 12

the Earth rotates fully in a 24h period

Question 13

The group of constellations that the Sun moves through over the course of a year are called

Answer 13

zodiac

Question 14

There are roughly 6000 stars visible to the naked eye from our planet. Over the course of the year you meticulously track all the stars that you can see and find that you can only ever see 3000 of them. Your location on Earth is

Answer 14

either the North or South Pole

Question 15

In the Northern hemisphere, the altitude of the North Star, Polaris, is always equal to

Answer 15

your latitude

Question 16

You find yourself at a latitude of 20o N. The circumpolar region would be:

Answer 16

70N to 90 N

Question 17

In the northern hemisphere, except very near the equator, the asterism Little Dipper which contains the star Polaris would be

Answer 17

circumpolar

Question 18

An object in the sky at its greatest possible altitude is ALWAYS

Answer 18

crossing the meridian

Question 19

The 88 sectors into which astronomers today have divided the the celestial sphere are called

Answer 19

constellations

Question 20

The ecliptic and the celestial equator are situated

Answer 20

At an angle of 23.5o to each other on the celestial sphere

Question 21

The strip of sky through which the Sun moves over the course of the year is called

Answer 21

the zodiac

Question 22

It’s 10:00 pm and the star Vega is just setting in the West. Tomorrow, we will observe Vega to set at

Answer 22

9:56 pm

Question 23

For the “chewing gum as a cure for headache” discussion, the placebo effect

Answer 23

is important to account for as a significant number of participants would believe their symptoms would improve

Question 24

Dr. Moody’s hypothesis was that similarities in stories told by those with near death experiences implied that there was life after death. On major flaw with his study was

Answer 24

he asked only Americans who have a shared culture and common beliefs

Question 25

Just before the Trinity test (of the first atomic bomb), Enrico Fermi decided he wanted a rough estimate of the blast's power before the diagnostic data came in. So he dropped some pieces of paper from his hand as the blast wave passed him, and used this to estimate that the blast was equivalent to 10 kilotons of TNT. His guess was remarkably accurate for having so little data: the true answer turned out to be 20 kilotons of TNT. Fermi had a knack for making roughly-accurate estimates with very little data and the types of problems this is applied to are called Fermi problems. Which of the following things is FALSE for the method of solving such problems?

Answer 25

you must generally resort to looking up many of the facts and assumptions

Question 26

Which of the following concerning Kepler's laws is FALSE?

Answer 26

he derived his three laws from Newton's equations

Question 27

In an ellipse, the semi-major axis is

Answer 27

half of the longest axis through the ellipse center

Question 28

According to Kepler's laws, when a planet is nearer aphelion in its orbit,

Answer 28

it is moving its slowest in its orbit

Question 29

According to Kepler's 3rd law, there is a relationship between the time it takes a planet to revolve around the Sun and its

Answer 29

average distance from the Sun

Question 30

Using Kepler's third law, which of the following statements is TRUE for a planet of period 3 years?

Answer 30

It's semi-major axis (or average distance from the Sun) cubed would equal 9

Question 31

Kepler's third law as he stated it wasn't quite correct. He was missing

Answer 31

the masses of the orbiting object and objected being orbited

Question 32

Professor Scully suggested hitting every branch of a tree if falling from a great height because

Answer 32

Newton's 3rd law insures I slow down a little after each branch strike

Question 33

Newton's first law of motion says that in order to change the direction of motion of an object, one needs to apply

Answer 33

an external force

Question 34

Which of the following statements about forces is FALSE?

Answer 34

in the absence of forces, objects tend towards rest

Question 35

I have twice the mass of a fellow ice skater. I push off on the other skater. Which of the following statements about what happens after we separate is TRUE?

Answer 35

we move in opposite directions with me moving half as fast

Question 36

Which of the following is FALSE concerning the acceleration due to gravity, g?

Answer 36

It has a different value on differing objects depending on their masses

Question 37

Which of the following statements concerning the force of gravity is FALSE?

Answer 37

its strength is inversely proportional to the mass: the more mass, the less gravity

Question 38

The Moon magically is transported to a distance 5 times further than its initial orbit from the Earth but nothing else changes. The relative strength of gravity

Answer 38

decreases by a factor of 25

Question 39

The mass of the Moon quadruples but the distance remains the same between it and the Earth. What is the strength of the gravitational force between the Earth and Moon relative to the original configuration?

Answer 39

4 times

Question 40

Suppose the mass of the Moon doubles and its distance from the Earth also doubles. The relative gravitational force between the Earth and the Moon

Answer 40

is 1/4 as much

Question 41

Which of the following is FALSE concerning the key developments in understanding planetary orbits?

Answer 41

The key features of Newton'a law of gravity were inspired from an object falling from the sky

Question 42

I am in my space capsule orbiting some distance from the Earth. I maneuver my craft to be in a lower orbit (closer to the Earth). I would find that in order to maintain this new orbit, my spacecraft would be moving (think about the mass on a string circling around)

Answer 42

faster

Question 43

Astronauts float in space in orbit around the Earth because

Answer 43

they are actually falling around the Earth

Question 44

Which of the following is a FALSE statement concerning the escape speed?

Answer 44

it is faster than the speed of light

Question 45

Neptune was discovered largely due to

Answer 45

the gravitational effects on Uranus allowed a prediction of its position

Question 46

According to Kepler's first law, position of the Sun is

Answer 46

always at one of the focus points of the ellipse

Question 47

Thee real meaning behind Kepler's second law of equal areas swept out in equal times is

Answer 47

that a planet moves faster near the Sun and slower farther away

Question 48

A newly discovered planet within our solar system is found to have an orbital period of 8 years. It's average distance from the Sun is

Answer 48

4 A.U.

Question 49

I am listening to a radio station of frequency 1000 kHz (or 1,000,000 Hz). What is the corresponding wavelength (c = 3 x 10^8 m/s)?

Answer 49

300 m

Question 50

Which of the following statements about the speed of light is false?

Answer 50

It may be different in different places and times in the universe

Question 51

Which of the following statements concerning the nature of an atom is FALSE?

Answer 51

electrons can orbit at any distance from the nucleus

Question 52

Two versions of an element that differ in terms of number of neutrons are called

Answer 52

isotopes

Question 53

Which of the following statements about electromagnetic radiation is FALSE?

Answer 53

all wavelengths of electromagnetic radiation carry the same energy

Question 54

The distance between the crests of the waves in the light we see is

Answer 54

the wavelength

Question 55

Which of the following has the longest wavelength?

Answer 55

Radio

Question 56

Why must we place telescopes in space to measure gamma-rays, X-rays, and some UV?

Answer 56

our atmosphere blocks these wavebands

Question 57

During a fashion show, you spot models wearing a yellow dress, a red dress, and a blue dress. The reflected light with the highest frequency is

Answer 57

the blue dress

Question 58

Which of the following statements concerning photons is FALSE?

Answer 58

they are all blocked by the earth's atmosphere regardless of frequency

Question 59

Which of the following concerning light is FALSE?

Answer 59

Galileo first measured its speed using lamps separated by great distances

Question 60

When comparing blackbodies of 5000 K and 10,000 K, which of the following statements is FALSE

Answer 60

the 5000 K blackbody's color would be at a shorter wavelength than that of the 10,000 K blackbody

Question 61

The Sun has a temperature of 5800 K. Wein's law tells us that the wavelength of peak emission is...

Answer 61

517nm

Question 62

Why do different types of elements give off or absorb different spectral lines?

Answer 62

the spacing of energy levels for electrons is different in each element

Question 63

A particular cloud of gas sees its electrons within its atoms falling from higher energy levels to lower energy levels more on average. We would observe

Answer 63

an emission line spectrum

Question 64

How are absorption lines produced in a spectrum?

Answer 64

a cool gas sits in front of a continuous source filtering out the specific wavelengths that translate to the jumps in energy levels

Question 65

A light bulb brightness is measured at 1 m distance and at 10 m distance. The brightness at 1 m vs. 10 m would be measured to be

Answer 65

100x brighter

Question 66

Suppose a star doubles in temperature (2x) but remains the same radius. It's brightness:

Answer 66

increases by 8x

Question 67

Suppose a star doubles in radius (2x) but remains the same temperature. It's brightness:

Answer 67

increases by 4x

Question 68

The energy carried by a photon of light is greatest for which waveband?

Answer 68

gamma-rays

Question 69

An atomic spectrum here on Earth for a particular elemental species shows an emission line at 500 nm. While observing a galaxy through a telescope, that emission line is found to be at 550 nm. We can say that

Answer 69

the galaxy is moving away from us

Question 70

An atomic spectrum here on Earth for a particular elemental species shows an emission line at 500 nm. While observing a galaxy through a telescope, that emission line is found to be at 550 nm. The speed the galaxy is moving is

Answer 70

.1c

Question 71

The speed of light is c = 3 x 108 m/s. You expect to see an absorption line for a particular element at 1000 nm as measured at rest. Instead you find that it is at 1100 nm. You conclude that the speed of the object is moving

Answer 71

0.1c or 30,000,000 m/s AWAY from you

Question 72

The earliest telescopes used by astronomers were:

Answer 72

refractors

Question 73

Which of the following is NOT a reason to place a telescope in space?

Answer 73

it's easier to build larger mirrors in space than on the ground

Question 74

The most important function of a telescope is

Answer 74

light gathering

Question 75

Which of the following is not an advantage of a telescope constructed with a mirror instead of a lens

Answer 75

mirrors filter out UV light

Question 76

JMU's 14" Celestron telescope has a focal length for its primary mirror of about 4000 mm. To magnify objects through the telescope to 500x, we would choose an eyepiece of focal length

Answer 76

8 mm

Question 77

Telescope A has a diameter of 2 m while telescope B has a diameter of 4 m. We can say that

Answer 77

telescope B collects 4x more light

Question 78

Which of the following concerning telescope resolution is FALSE

Answer 78

The smaller the observed wavelength, the worse the resolution

Question 79

Radio telescopes cant make out detail per dish size anywhere near their optical counterparts due to the dependence of resolution on wavelength. To overcome this

Answer 79

astronomers use multiple connected dishes whose effective diameter is the same as the width of the array

Question 80

Which of the following concerning interferometry is FALSE?

Answer 80

Greenbank is the largest interferometer in the world

Question 81

Which of the following concerning telescope construction is FALSE

Answer 81

mirrors are less efficient than lenses

Question 82

Radio telescopes focus radio waves using

Answer 82

a dish formed of a conducting material

Question 83

Which of the following statements concerning recent advances in telescopes is FALSE

Answer 83

JWST is the largest ground-based telescope ever built

Question 84

CCDs are superior to film in all of these ways except one. Select it

Answer 84

CCDs only use 1% or so of the light which is better for exposure

Question 85

To break up light into its component wavelengths, astronomers attach to the telescope

Answer 85

a spectrograph

Question 86

All of the following are important when choosing the location of an observatory EXCEPT

Answer 86

we want to be closer to the poles to see half the sky

Question 87

A technique called adaptive optics allows astronomers to:

Answer 87

compensate for changes in the Earth's atmosphere and achieve better resolution

Question 88

Which of the following types of telescopes can be used ONLY above the Earth's atmosphere?

Answer 88

x-ray telescopes

Question 89

The most common element in the Sun is

Answer 89

hydrogen

Question 90

The part of the Sun we see here on Earth is the

Answer 90

the photosphere

Question 91

Which part of the Sun's atmosphere is the hottest?

Answer 91

the corona

Question 92

Solar wind particles can be captured by the Earth's magnetic field. When they spiral down into the atmosphere, they are responsible for

Answer 92

aurorae

Question 93

Astronomers now realize that active regions in the Sun's atmosphere are connected with

Answer 93

the Sun's magnetic field

Question 94

On Earth, periods of lower solar activity such as the Maunder Minimum means

Answer 94

cooler temperatures

Question 95

Which of the following are NOT part of the active regions on the Sun?

Answer 95

radiative zone

Question 96

Sunspots are darker than the regions of the Sun around them because

Answer 96

they are cooler than the surrounding material

Question 97

Astronomers have concluded that the Sun's activity varies in an 11-year cycle. Which of the following statements about this cycle is TRUE?

Answer 97

The number of sunspots cyclically gets larger and smaller over the course of 11 years

Question 98

A friend (who does not have the new awareness which you have gained from this course) suggests that the mechanism that keeps the Sun shining as brightly as it does is the burning of coal. You challenge his theory! Your challenge comes in several related steps; which of the following is one of those steps?

Answer 98

the dating of radioactive rocks show that the Earth and thus the Sun are billions of years old and so you must determine if there is sufficient fuel

Question 99

Ultimately the Sun is powered by

Answer 99

fusion of hydrogen into helium

Question 100

On average, it takes a photon produced in the core ___________ years to reach the surface of the Sun.

Answer 100

close to a couple hundred thousand years

Question 101

When energy is first produced by fusion deep in the core of the star, that energy moves outward mostly by what process?

Answer 101

radiation

Question 102

The final 30% or so of the trip to the surface of the Sun, energy is transported mainly by

Answer 102

convection

Question 103

Our notion about what ultimately powers the Sun has been proven by the appropriate detection of

Answer 103

neutrinos

Question 104

According to the formula E=mc2

Answer 104

a little bit of mass can be converted into a substantial amount of energy

Question 105

The process of fusion that keeps our Sun shining begins with which building blocks?

Answer 105

two protons

Question 106

At the end of the p-p chain of nuclear fusion in the Sun, hydrogen nuclei have been converted into

Answer 106

helium-4

Question 107

The Sun is an enormous ball of gas. Left to itself, a ball of so many atoms should collapse under its own tremendous gravity. Why is our Sun not collapsing?

Answer 107

nuclear fusion in the core keeps the temperature and the pressure inside the Sun at a high enough level so that gravity is balanced