Physics JeopardyWaves Waves

Wave Calc Sound Extra credit on quiz questions

Q $100

Q $200

Q $300

Q $400

Q $500

Q $100 Q $100Q $100 Q $100

Q $200 Q $200 Q $200 Q $200

Q $300 Q $300 Q $300 Q $300

Q $400 Q $400 Q $400 Q $400

Q $500 Q $500 Q $500 Q $500

Final Jeopardy

$100 Waves

• Where can you touch a standing wave on a rope without disturbing the wave?

$100 Answer Waves

• At any of the nodes

$200 Waves

• As the sound of a car’s horn passes and recedes from you, the pitch of the horn seems to _______.

$200 Answer Waves

• Decrease

$300 Waves

• The Frequency of this wave is _________.

3 m

1 m

0.5 s

$300 Answer Waves

• 2 Hz

$400 Waves

• What is a sonic boom?

$400 Answer Waves

• A 3D wave pattern that is produced as the source of a wave moves faster than the wave it produces.

$500 Waves

Suppose a simple pendulum is suspended in an elevator. When the elevator is accelerating upward, the period of the pendulum __________.

$500 Answer Waves

• Decreases

$100 Question Waves

• The amplitude of this wave is _________.

3 m

1 m

0.5 s

$100 Answer Waves

1 m

$200 Question Waves

During a single period of a wave, how far does it travel?

$200 Answer Waves

One wavelength

$300 Question Waves

As the speed of a wave in air changes, its frequency will _______.

$300 Answer Waves

It shouldn’t do anything. As frequency changes wavelength changes, but the speed of a wave in a medium is constant.

$400 Question Waves

What does it mean for two waves to be 180 degrees out of phase? What happens to these two waves?

$400 Answer Waves

They cancel out

$500 Question Waves

I drop an elephant off a boat in the middle of the Atlantic ocean. Explain why, if energy is conserved, why the wave most likely wont reach you in cape cod?

$500 Answer Waves

The energy spreads out

$100 Question Wave Calc.

The wave speed of this wave is _________.

3 m

1 m

0.5 s

$100 Answer Wave Calc.

6 m/s

$200 Question Wave Calc.

If you double the frequency of a vibrating object, its period __________.

$200 Answer Wave Calc.

halves

$300 Question Wave Calc.

Katie pushes Micah on a swing in an attempt knock Forrest over on the other side of the swing set. If it takes Micah 1.4s to hit Forrest, how long is the swing?

$300 Answer Wave Calc.

.69 m

$400 Question Wave Calc.

Radio amateurs are permitted to communicate on the 10 meter band. What frequency of radio waves corresponds to a wavelength of 10m if the speed of light is 3x108m/s?

$400 Answer Wave Calc.

3x10^7 Hz

$500 Question Wave Calc.

As an anchor is being hoisted out of the water, it hits the hull of a ship, causing the anchor to vibrate with a frequency of 150 Hz. If the speed of sound in sea water is 1520 m/s, how many wavelengths of sound will fit between the boat and the ocean bottom 395 m below?

$500 Answer Wave Calc.

38.98 m

$100 Question Sound

A sound wave is what kind of wave?

$100 Answer Sound

Longitudinal or compression

$200 Question Sound

What is the resonant frequency of a 350 Hz tuning fork if it is struck on a 25 degree Celsius day?

$200 Answer Sound

350 Hz

$300 Question Sound

How many times more intense is a 80 dB sound than a 60 dB sound?

$300 Answer Sound

100 times

$400 Question Sound

Laura is going to drop a pie on your head from a high altitude. To stop you from getting pied, Jack tries to sabotage Laura by placing a buzzer in the pie. The buzzer creates a tone of about 19,700 Hz. Do you think you will get hit with the pie? Why?

$400 Answer Sound

Yes, since the pie is traveling toward you, the frequency increases due to the Doppler Effect. A human can’t hear over 20,000 Hz and has trouble even with frequencies approaching that so most likely you wont hear it coming.

$500 Question Sound

Two notes are sounding, one of which is 370 Hz. If a beat frequency of 5 Hz is heard, what is the other note’s Frequency?

$500 Answer Sound

365 Hz, or 375 Hz

$100 Question Other

Draw a picture of the second harmonic on a string of length 2 meters

$100 Answer Other

2m

$200 Question Other

What direction will point E move as this wave progresses?

$200 Answer Other

Downward

$300 Question Other

A whale makes a bellowing sound that is with in the subsonic frequency. This means that it is below what frequency of sound?

$300 Answer Other

20 Hz

$400 Question Other

Draw the third harmonic of a wave that fits into a flute (two open ends) that has a length of .3 m. Draw this wave and record the wavelength.

$400 Answer Other

.2m

$500 Question Other

A torpedo fired from a submerged submarine is propelled through the water with a speed of 20.0m/s and explodes upon impact with a target 2000m away. If the sound of the impact is heard 101.4 s after the torpedo was fired,what is the speed of sound in water ? ( Because the torpedo is held at a constant speed by its propeller, the effect of the water resistance can be neglected.)

$500 Answer Other

V= 1428.5 m/s

Final JeopardyWhat does the fact that some starts look blue and some stars look red indicate about motion of the star… and why?

Final Jeopardy AnswerDue to the Doppler Effect, starts moving away from us have lower frequencies so they appear red and stars moving toward us have higher frequencies so they look blue.