Download - Have you ever taken a physics course before? Do you play an instrument? Can you read music?
• Have you ever taken a physics course before?
• Do you play an instrument?
• Can you read music?
Why are you taking this class?
Do you have an Iclicker?
A) Yes, I do!B) Not yet…
(Please register it, see our web page)
CT 1.0.2
To do well in this class, how many hrs/week do you expect to spend outside of lecture?
a) < 2 hrs each weekb) 2-4 hrsc) 4-6 hrsd) 6-8 hrse) 8+ hrs
CT 1.0.1
How do you think you will learn physics the best?
a) Listening to lecture
b) Reading the textbook
c) Doing the homework
d) Discussing with others
e) Other…
CT 1.1.1
If a tree falls down in some remote forest does it make a sound?
a) Yes
b) No
c) Maybe
d) I don’t really understand what this question is trying to ask!?
CT 1.1.2
The following sound would be classified as:
a) Musical
b) Speech
c) Noise
d) Organized sound
e) Transient
CT 1.2.2
If I whack a ruler hanging off the desk, I can make a “note”.
What happens if I move it back so less hangs off the edge, but I whack it just as hard?
A) Pitch , loudness similar
B) Pitch similar, loudness
C) Pitch , loudness
D) Pitch , loudness similar
E) Something else
WHY?
CT 1.2.3
What determines pitch?Which is the most important feature of the
instrument/source of sound?
A) Length/size
B) “Bendability”/rigidity
C) Heaviness/density of material
D) Amplitude (how hard it is struck)
E) More than one of the above
A-B: very (equally) important
C: Depends!
D is a special case… but usually does NOT matter (much).
CT1.2.4
Let’s fill the Tibetan singing bowl with water. What happens to the pitch of
the tone it makes?
A) goes up
B) goes down
C) pretty much unchanged
D) no way to know this without trying
Why?
CT 1.4.7
Which sounds travel the fastest through air?
a) Higher pitchb) Lower pitchc) Louder soundsd) Quieter soundse) They all travel at the same speed
And a darn good thing…
Speed of sound
(344 m/s in room temperature air.)
CT 1.4.1
Approximately how close is a thunderstorm
if you see lightning flash and hear a clash of thunder after counting up to 6 seconds? (the speed of sound is 344 m/s)
a) 0 km
b) 1 km
c) 2 km
d) 6 km
e) None of these
CT 1.4.2
You are traveling on a commercial airplane (say
a Boeing 757). Relative to the speed of sound
you are traveling:
a) much slower than sound
b) a little slower than sound
c) the same speed as sound
d) a little faster thaqn sound
e) much faster than sound
CT 1.4.4
In which of the following venues can you noticea difference between the music you perceiveand the movements of the musicians (i.e. can you tell that the sound has traveled a distance?)
a) The rear of the Fox Theater b) Pepsi Centerc) Red Rocks amphitheaterd) All of the above
Textbook says about 20 meters (about 60 feet, about the width of the grass field in the stadium) is where most people start to notice «lag».
CT 1.4.5
In a 32 o C room sound travels…
a) > 344 m/sb) 344 m/sc) < 344 m/s
Speed depends on the temperature Depends on the medium(Faster through solid metal than
through air, e.g!)
What if the room is 32o F? Does the sound travel faster or slower than a 32o C room?
a) Fasterb) Slowerc) Same speed
Do you need to know temperature if you want to directly measure the speed of sound (by measuring distance traveled and time taken)?
A) Yes
B) No
CT 1.4.6
When sound travels from a source to a listener,
what do air molecules never do?
a) Travel from the source to the listener at 344 m/s
b) Move back and forth with the frequency of the sound wave
c) Bump into other air molecules
d) Move in the direction of wave propagation
e) Air molecules do all of the above
CT 1.4.3
Sound travels at a speed of 344 m/s (770 mph).
How fast does the air flow out of my mouth as I
speak?
a) Much slower than 344 m/s
b) 344 m/s
c) Much faster than 344 m/s
CT 1.5.2
I stand on a scale with both feet and measure my weight. If I stand on one foot, does the reading:
a) Increaseb) Decreasec) Remain the samed) ???
When I stand on one foot, does the
pressure on the other foot (the one that remains on the ground)…
a) Increase
b) Decrease
c) Remains the same
d)??
CTR1.3
You’re clapping in front of a wall, a distance “D” away from you. The pattern is clap-pause-echo-pause-clap-pause-echo…
(evenly spaced… picture it!) Your friend times your claps (not the echos!) and counts 6 claps in 10 seconds. What’s the speed of sound?
A) 4 D / (0.6 sec)B) 2 D / (0.6 sec)C) D / (0.6 sec)D) 10 D / (.6 sec)E) D / (1.2 sec)
How fast (frequently) can you tap the desk?
(What’s your clapping frequency in Hz?)
CT 2.1.3
If I lower the frequency of this tone what happens to the pitch?
a) It decreasesb) It increasesc) It remains the samed) Not enough information
What if I make the same sound louder
(keeping the same pitch),
the frequency…
CT 1.5.1
If there is really a force of 105 N (that’s
100,000 N, about 11 tons!) on each square meter of a glass window, why is it that the window does not shatter?
a) That is such a small force it does not matter
b) Other forces (e.g. from the frame) counteract and balance this
c) Glass is stronger than you think
d) There is an equal but opposite force of air pushing against the window from the other side
e) Gravity counteracts the force
CT 1.5.3alt
a) I weigh 500 N, what is the force on each foot?
a) 500 N each
b) 250 N each
c) It depends on the area of my foot
CT 1.5.4
Who is more likely to damage a hardwood
dance floor, while just standing around?
a) A 250 lb person wearing boots with 2 cm x 2 cm heels
b) A 100 lb person wearing 1 cm x 1 cm heels
c) They will do equal damage
d) Not enough information to make an informed choice
(Pressure = Force/ area)