Name: ___________________________________________________ Period: ____________

Table #: _____________

Unit 2:Intro to Waves Slinky Waves Water Waves

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Worksheet 1 1. The illustration below shows a series of transverse waves. Label each part in the space provided. a. b. a b c. c d. e. e f f. d g g. Fill in the blanks: 2. Waves carry

from one place to another.

3. The highest point on a transverse wave is the 4. The

while the lowest part is the

.

is the height of the wave.

5. The distance from one crest to the next is the

.

6. Below are a number of series of waves. Underneath each diagram write the numbers of waves in the series. A C B . . D . .

a. Which of the above has the biggest amplitude? b. Which of the above has the shortest wavelength? c. Which of the above has the longest wavelength? 7. Consider a wave generator that produces 10 pulses per second. The speed of the waves is 300. cm/s. a. What is the wavelength of the waves?

b. What happens to the wavelength if the frequency of pulses is increased?

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8. A wave on Beaver Dam Lake passes by two docks that are 40.0 m apart. a. If there is a crest at each dock and another three crests between the two docks, determine the wavelength.

b. If 10 waves pass one dock every 16.0 seconds, determine the period and frequency of the wave.

c. What is the speed of the wave? 9. Sally Sue, an enthusiastic physics student enjoyed the opportunity to collect data from standing waves in a spring. She and her partner held the ends of their spring 4.00 meters apart. There were 5 nodes in the standing wave produced. Sally moved her hand from the rest position back and forth along the floor 20 times in 4.00 s. Sketch the situation below and determine the following: a. the wavelength of the wave Sally Sue sent

b. the frequency of the wave produced

c. the speed of the wave

10. What frequency and period would be required for Sally and her cheerful, pleasant, hard-working partner to produce a standing wave with three nodes? Explain your reasoning by identifying your steps.

11. The wavelength of a sound wave in this room is 1.13 m and the frequency is 301 Hz. a. What is the speed of the wave in the room?

b. If you double the frequency of the sound wave, determine its speed.

c. What happens to the wavelength if you cut the frequency in half? How do you know?

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Lab 1: Waves- Internet Lab Purpose: During this internet simulation, you will follow the steps below to gain a basic understanding of waves by analyzing waves created in a slinky. Part I: Speed - How fast the energy travels Purpose: To determine what factors affect the speed of a wave on a string Set-Up: Go to the web site http://phet.colorado.edu/simulations/sims.php?sim=Wave_on_a_String • Click on the green ‘Run Now’ • Move the DAMPING to Zero • Click on PULSE mode (not manual or oscillation) • Click on NO END Investigation: • Change the parameters (only 1 at a time) and see if that parameter changes the speed of the wave. Change that parameter 3 times. Questions: Answer these questions on the separate LAB ANSWER SHEET in your packet 1) What factor(s) affect the speed of a wave on a string? 2) Does the medium move along with the wave? If yes, how do you know? And if no, what does move? 3) Would the type of slinky used (plastic opposed to steel) affect the speed of the wave if all other factors were held constant? How do you know? Part II : Reflection - Energy bouncing off a barrier Purpose: To determine what occurs to a pulse when it undergoes fixed and free end reflection. Set Up: • Keep DAMPING at Zero • Click on FIXED END • Click on PULSE mode (not manual or oscillation) Investigation: • Send a pulse down the string and observe what happens on a FIXED END Reflection. • Measure the speed of the incident pulse (before it hits the barrier) and the speed of the reflected pulse (after it hits the barrier). Do 3 trials and record in a table • Click on LOOSE END, and send a pulse down the string and observe what happens on FREE END • Observe the speed of the incident pulse and reflected pulse. Questions: Answer these questions on the separate LAB ANSWER SHEET in your packet 1) What happens to the pulse amplitude on FIXED END reflection? 2) What happens to the pulse amplitude on FREE END reflection? 3) What happens to the speed of the reflected wave compared to the speed of the incident wave? 4) In the LOOSE END simulation, were both ends of the string loose? How do you know? 4

Part III: Interference – 2 or more waves meeting Purpose: To determine what occurs when pulses undergo interference. Set Up: • Keep DAMPING at Zero • Click on LOOSE END • Click on PULSE mode (not manual or oscillation) Investigation: • Send a pulse down the string and then a short time later send another pulse down. • Click the PAUSE/PLAY button after the first pulse gets reflected back towards the second just before they are about to hit • Click the STEP button and observe what happens to the 2 waves when they meet.. Since both pulse amplitudes are on the same side, this is called Constructive Interference. • Click the PAUSE/PLAY button so that the simulation continues. • One wave will travel towards the left and will undergo fixed end reflection and flip itself over and approach the other wave. • Click the PAUSE/PLAY button just before they are about to hit. • Click the STEP button and observe what happens to the 2 waves when they meet. Since each pulse amplitudes are on the opposite side, this is called Destructive Interference. • Click on Manual and reset • To manually create a pulse you click and drag up and down. • Generate a large amplitude and then generate a small amplitude or 2 distinctive wave pulses • Observe what happens after they meet. • Do 3 different trials Questions: Answer these questions on the separate LAB ANSWER SHEET in your packet 1) Summarize what happens to the amplitudes during constructive interference. Use terms of amplitude ‘A’ and amplitude ‘B’. 2) Summarize what happens to the amplitudes during destructive interference. Use terms of amplitude ‘A’ and amplitude ‘B’. 3) What happens to the amplitudes after the pulses meet?

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Worksheet 2 Reflection/Transmission 1. a. In the box below, draw the pulse as it returns after reflecting from a fixed end.

b.

Draw the pulse as it returns after reflecting from a free end.

b.

Draw the pulse as it returns after reflecting from a free end.

2. a. Draw the pulse as it returns after reflecting from a fixed end.

3. Two students each holding an end of a slinky spring are 5.0 m apart. It takes 0.60 seconds for a transverse pulse to travel from the student generating the pulse to the lab partner at the opposite end of the spring. a. How long will it take for the reflected pulse to return to the generating student?

b. When a second pulse of twice the original amplitude is sent, will the pulse take more time, less time, or the same time to reach the far end of the spring? Explain your answer.

c. The students move so that they are now farther apart but use the same spring. Compare the speed of a pulse on the more stretched spring to the speed of the pulse when they were 5.0 m apart. Explain your answer. 4. The diagram to the right shows a pulse traveling from a “light” string to a “heavy” string. In the box below, draw the reflected and transmitted pulses after the original pulse has reached point P.

P

P

5. The diagram to the right shows a pulse traveling from a “heavy” string to a “light” string. Draw the reflected and transmitted pulses after the original pulse has reached point P.

6. Below is a pulse in a light rope approaching a heavy rope. Sketch the two rope system just after the pulse hits the wall. AFTER

wall

wa

Before

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7. To the right is a two-rope system soon after it was shaken. a) If the right rope is the heavy rope, determine which end was shaken and whether it was a crest or a trough. b) If the left rope is the heavy rope, determine which end was shaken and whether it was a crest or a trough. 8. On the lines below draw the pulses as they would appear after they have completed their reflection from the end. Slanted lines, (//), following the barrier line represent a fixed end. Otherwise the barrier is a “free end.” Before After

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Worksheet 3 Fill in the table below using the concept of principle of superposition. For each impulse given, determine if it is an example of constructive or destructive interference, Draw the impulse of object A and B when they are AT interference and AFTER they have passes through. Impulses Heading Constructive or Draw Impulse AT Draw Impulse AFTER toward EACH OTHER Destructive? Interference Interference (label which one is A and B) 1.

A

B

2. A

B

A

B

3.

4. A

B 5. A

B

6. B A 7. A

B

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Lab 2: Waves- Virtual Ripple Tanks Purpose: To investigate different wave properties using water as the medium You will: Create all diagrams and answer all questions on your lab answer sheet on page ______ in your packet labeling IWD (Incident Wave Direction), IWF (Incident Wave Front), RWD (Reflected/Refracted Wave Direction) and RWF (Reflected/Refracted Wave Front) * Use different colors for each of these* Task 1: Getting to know the program with your teacher Open the site • http://www.falstad.com/ripple/ • Listen to teacher instructions and use the space below to take any notes of what you need to do for part A and part B below. • Play with some of the different functions but DO NOT ADJUST THE SLIDE BARS IN THE LOWER RIGHT HAND CORNER UNLESS INSTRUCTED TO DO SO. Part A. Diagramming Straight Waves Notes for Completing Part A:

Part B. Diagramming Circular (Point) Waves Notes for Completing Part B:

On Your Answer Sheet: o Diagram wave front & wave direction for Part A and B o What is the relationship between the wave front and the wave direction for Part A and B?

Wheaton North: Physics I

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Unit 2 - Packet

Task 2: Wave REFLECTION off of a different barriers Observe and sketch IWF, IWD, RWF, RWD for each setup below Part A. Straight waves off straight barriers • Select No Sources • Create a barrier (do a parallel barrier first then repeat with an angled barrier) using your mouse (Mouse = Edit Walls) • Create a Wave using your Mouse (Mouse = Edit Wave) • Use your mouse and generate a straight wave. • Use the STOPPED function to pause the simulation in order to make your drawings • After each trial, Clear Walls and Clear Waves

*Send wave into barrier*

*Send wave into barrier*

Parallel Barrier

Angled Barrier

On Your Answer Sheet: o Diagram the IWF, IWD, RWF, & RWD for the parallel and angled barrier o What is the relationship between the angle it hits the barrier with and the angle it leaves the barrier with? Part B. Straight waves off curved barriers • Use Setup: Circle o Select No Sources o Create a Wave using your Mouse (Mouse = Edit Wave) • Use your mouse and generate a straight wave. • Use the STOPPED function to pause the simulation in order to make your drawings • After each trial, Clear Walls and Clear Waves • For the Convex barrier, create the wave OUTSIDE the circle • For the Concave barrier, create the wave insides the circle

Convex Barrier

Concave Barrier

On Your Answer Sheet: o Diagram the IWF, IWD, RWF, & RWD for each o Which waves converge… concave or convex?? What happens after they converge? o Experiment by creating a wave at different locations. Does it change your results

Wheaton North: Physics I

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Task 3: Wave REFRACTION Observe and sketch IWF, IWD, RWF, RWD for each setup below Part A. Straight waves PARALLEL to medium change • Use Setup: Slow Medium o Select: 1 Plane 1 Freq w/Phase • Use the STOPPED function to pause the simulation in order to make your drawings

H2O flow direction medium change On Your Answer Sheet: o Diagram the IWF, IWD, RWF, & RWD o What changes when you go from one medium to another? How do you see this change? What causes this change? What is staying the same? o Is the second medium “more dense” or “less dense”? o Do you think the second medium is shallow water or deep water? Why?

Part B. Straight waves at an ANGLE to the medium change • Use Setup: Refraction • Use the STOPPED function to pause the simulation in order to make your drawings H2O flow direction medium change

On Your Answer Sheet: o Diagram the IWF, IWD, RWF, & RWD o Does the direction of the wave change? o What happens to the wavelength as the wave travels from one medium to the other? o Why does the wave change direction? o Predict what would happen to the wavelength as the wave travels from the second medium to the first. Draw a diagram!

Wheaton North: Physics I

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Task 4: Wave DIFFRACTION Observe and sketch IWF, IWD, RWF, RWD for each setup below Part A. Straight waves through an opening – Changing Frequency • Use Setup: Single Slit • Adjust the slide bar for frequency both higher and lower than the original to change frequency • Use the STOPPED function to pause the simulation in order to make your drawings On Your Answer Sheet: o Diagram the WF & WD o What changes when a wave passes through the opening? o For a constant width, how does the amount of diffraction vary with increasing frequency? o For a constant width, how does the amount of diffraction vary with increasing wavelength? Part B. Straight waves through an opening – Changing Opening Width (constant frequency) • Create a smaller opening using your mouse (Mouse = Edit Walls) • Set the frequency at a medium pace • Use the STOPPED function to pause the simulation in order to make your drawings On Your Answer Sheet: o Diagram the WF & WD o For a constant frequency, how does the amount of diffraction vary with increasing width? Task 5: Wave INTERFERENCE • Use Setup: Two Sources • Use the STOPPED function to pause the simulation in order to make your drawings Part A. Changing frequency / Fixed source separation • Count the number on nodal lines in the pattern. • Change the wavelength by changing the frequency and observe the change in the pattern. • Count the number of nodal lines (Gray parts of the wave) • Do this for at least 4 different frequencies. On Your Answer Sheet: o What is the relationship between frequency and number of nodal lines? Part B. Fixed frequency / Changing source separation • Choose a medium frequency and count the number of nodal lines in the pattern. • Keeping the frequency constant move the point sources slightly further apart and observe the nodal and anti-nodal lines. • Count the number of nodal lines. • Do this for at least 4 positions of source separation. On Your Answer Sheet: o What is the relationship between source separation and number of nodal lines? Wheaton North: Physics I

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Unit 2 - Packet

Review Worksheet 1. Two students, 5.0 m apart, each hold an end of a long spring. It takes 1.2 seconds for a pulse to travel from the student generating the pulse to the lab partner at the opposite end of the spring. a. How long will it take for the pulse to return to the “generator”?

b. Explain the motion of the pulse passing through the spring. Calculate the speed of the pulse.

2. The “generator” in Problem 1 repeats the experiment with a pulse of twice the original amplitude. Will the pulse take more time, less time, or the same time to reach the far end of the spring? Explain your answer.

3. The students move so that they are now twice as far apart but use the same spring. How will the speed of the pulse sent now compare to the speed of the pulse sent when they were 5.0 m apart? Explain your answer.

4. The illustration below shows a series of transverse waves. Label each part in the space provided. a. b. a b c. c d. e e. f d g f. g. 5. The graph below was produced by plotting data for the distance (d) a pulse traveled along a spring in time t. Write the mathematical model for the data graphed below. 12.0

d (m) 10.0 8.00 6.00 4.00 2.00

Wheaton North: Physics I

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Unit 2 - Packet 0.00 0.00

0.400

0.800

1.20

1.60

2.00

t (s) Statistics:

Slope

Y Intercept

C.O.R.

Questions 6 – 11 shows pulses A and B as they head toward each other. On the graph below each situation, show the position of pulse A (in red) and pulse B (in blue) at the instant the centers of the pulses overlap.

6.

7.

8.

7. 9.

9.

8.

1o.

11.

11. 13.

12.

12. Use the diagram of the standing wave of a string to answer the questions below. The string is 20 cm in length.

A. How many nodes are there?

B. What is the wavelength?

Wheaton North: Physics I

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13. Correctly diagram the following on Reflection off of an angled barrier in a Ripple Tank. Straight Waves Barrier

14. What will happen to the reflected waves off of this barrier? Straight

Curved Barrier

15. Correctly diagram the following on Refraction in a Ripple Tank. Straight

Deep Water

Shallow Water

16. For the Wave Diagrams below, sketch what the Diffracted wave front should look like. Be as specific as possible and make sure to show difference between each if appropriate. The size of the opening is the same for both diagrams. If you wanted to change the amount of diffraction, what else could you change and how would it effect the diffraction.

Wheaton North: Physics I

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Unit 2 - Packet

Calculation Answers for Unit 2 Packet Since you have the answers to these questions, your teacher will be looking for the work as you how you got to the answers to receive credit. Be sure to ALWAYS show ALL of your work for ANY calculations!!

Worksheet 1 8a. 10 m 8b. 0.625 Hz, 1.6 sec 8c. 6.25 m/s 9a. 2m 9b. 5 Hz 9c. 10 m/s 11a. 340.13 m/s 11b. 340.13 m/s

Wheaton North: Physics I

Unit Review Worksheet 1b. 4.16 m/s

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Unit 2 - Packet

Lab 1: Waves- Internet Lab Answer Page Part I: Speed - How fast the energy travels 1. What factor(s) affect the speed of a wave on a string?

2. Does the medium move along with the wave? If yes, how do you know? And if no, what does move?

3. Would the type of slinky used (plastic opposed to steel) affect the speed of the wave if all other factors were held constant? How do you know?

Part II: Reflection - Energy bouncing off a barrier 4. What happens to the pulse amplitude on FIXED END reflection?

5) What happens to the pulse amplitude on FREE END reflection?

6) What happens to the speed of the reflected wave compared to the speed of the incident wave?

7) In the LOOSE END simulation, were both ends of the string loose? How do you know?

Wheaton North: Physics I

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Unit 2 - Packet

Lab 2: Waves- Ripple Tank Answer Page ** Do your diagrams in PENCIL. Label ALL PARTS ** Task 1: Getting to know the program with your teacher Diagrams Straight Waves

Circular Waves

What is the relationship between the wave front and the wave direction for… a. straight waves: b. circular waves: Task 2: Wave REFLECTION off of a different barriers Diagrams Parallel

Angled

What is the relationship between the angle it hits the barrier with and the angle it leaves the barrier with?

Convex

Concave

Which waves converge…. concave or convex?? What happens after they converge? Experiment by creating a wave at different locations. Does it change your results? Wheaton North: Physics I

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Unit 2 - Packet

Task 3: Wave REFRACTION Diagrams Parallel

Angle

Parallel: What changes when you go from one medium to another? How do you see this change? What causes this change? What is staying the same?

Is the second medium “more dense” or “less dense”? Do you think the second medium is shallow water or deep water? Why? Angle: Does the direction of the wave change? What happens to the wavelength as the wave travels from one medium to the other? Why does the wave change direction? Predict what would happen to the wavelength as the wave travels from the second medium to the first. Draw a diagram! Task 4: Wave DIFFRACTION Diagrams Change Frequency

Change Opening

Answer the following with either increase, decrease or stays the same: 1. For a constant width, how does the amount of diffraction vary with increasing frequency? 2. For a constant width, how does the amount of diffraction vary with increasing wavelength? 3. For a constant frequency, how does the amount of diffraction vary with increasing width? Wheaton North: Physics I

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Unit 2 - Packet

Task 5: Wave INTERFERENCE What is the relationship between frequency and number of nodal lines?

What is the relationship between source separation and number of nodal lines?

Wheaton North: Physics I

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Unit 2 - Packet