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By: Claudia, Sydney, and Mary Clare ** How does sound interact with a medium? Hypothesis: That the sound waves do move through mediums. Pre-Lab Discussion The energy of a sound wave disturbs the molecules in a medium, making them rock back and forth in time with the wave frequency. When the vibrations are very fast, you hear a high-pitched sound called amplitude. > || Vibrations in a medium: •Made water splash || > || Similar vibrations: > || Resonance: •Buzzing noise || > || Interference: > || Beats: > || Moving sound:
 * __Tuning Forks GQ2__
 * Problem:
 * 1. What does sound do to the surrounding medium? **
 * 2. What property of a sound wave changes as it gets louder? **
 * ** Test ** || ** Loudness Change ** || ** Pitch Change ** || ** Effect ** ||
 * Yes || No || •It vibrated, stopped in water
 * Yes || No || •Made a deep sound ||
 * Yes || No || •Vibrates longer
 * Yes || No || •Sounds like a siren because it gets louder and quieter ||
 * Yes || No || •Rubber band stops vibration ||
 * Yes || Yes || •It got louder as it got closer to your ears ||

The amplitude changed in all the tests because the sound was moving through different mediums.
 * 1. **** Did the loudness of the sound change in some tested? If so, give examples and explain why the loudness changed? **

The distance decreases so the frequency increases. You need a controllable variable. Transfers energy through waves. It creates a constructive interference. They constructively interfere. Where its position is. Cycle Three Natural World Power > > > > > > > **Energy Conversions** **Materials:** · A Ramp · A Spring Scale · A Meter Stick · Tape · A LEGO Car · **Steps:** **1.) ** We built a car for our experiment. **2.) ** We got a ramp and leaned it up against a small box. **3.)** Then, we put the car on the top of the ramp and let go. **4.)** We measured how far the car had traveled. **5.)** Next, we put the car at a different height on the ramp and tested to see how far the car would go that time.  **6.)** We measured how far the car went the second time and compared our results. · **As the vehicle rolls down the ramp, what happens to the relationship between its potential and kinetic energy?** When the car rolled down the ramp, its energy changed from potential to kinetic. When the vehicle was at the top of the ramp, it had gravitational potential energy. When the vehicle was at the bottom of the ramp, it had kinetic energy. · **When the vehicle reached the bottom of the ramp, what happened to its potential energy and kinetic energy?** The potential energy increased while the kinetic energy decreased because of gravitational pull. · **What happened to the vehicle as it continued traveling on the floor?** The vehicle slowed down because it lost its speed. · **Mark the distance from the bottom of the ramp where the vehicle comes to a halt. Now release the car from** **¾** **up the ramp. Mark the distance from the bottom of the ramp where the vehicle comes to a halt. What is the difference in the two distances?** The difference in the two distances was six inches. When we started rolling the car down the ramp ¾ of the up, it traveled six less inches. · **How does the height that the vehicle is released from effect the distance the vehicle travels and why?** The steeper the ramp, the further the vehicle will travel because of gravity and friction. > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > Guiding Question One Experiments
 * 2. **** How did the pitch change in the moving-source test? Explain this observation? **
 * 3. **** Why did you experiment with two tuning forks that vibrate at the same frequency? **
 * 4. **** How does one vibrating object make another object vibrate, when they’re not touching? What is true of both objects’ vibrations when this happens? **
 * 5. **** Why does sound get louder with the use of the resonance box? **
 * 6. **** How are beats produced by two similar tuning forks? **
 * 7. **** Bats bounce sound waves off objects to get information about prey and obstacles. If a bat makes a constant-frequency sound and the sound bounces back with a different frequency, what does that change tell the bat about an object? **
 * Guiding Question One Notes

** Can You Feel the Power ** **Question**: How can you change how much power you expended while doing an exercise? **Experiment** A step was constructed 20 cm high. Students were asked to step up and down 20 times in succession at a constant rate with the time recorded. For the second trial, students were asked to step up and down at a slower pace. **Data Table** Justin || 90 lbs.; 401 N || 20 cm./ .2 m || 35 sec. || 80.2 J || 80.2 J || 2.29 W || Justin || 90 lbs.; 401 N || 20 cm./ .2 m || 49 sec. || 80.2 J || 80.2 J || 1.64 W || James || 90 lbs.; 401 N || 20 cm./ .2 m || 36 sec. || 80.2 J || 80.2 J || 2.22 W || James || 90 lbs.; 401 N || 20 cm./ .2 m || 41 sec. || 80.2 J || 80.2 J || 1.96 W || Susanne || 93 lbs.; 414 N || 20 cm./ .2 m || 40 sec. || 82.8 J || 82.8 J || 2.07 W || Susanne || 93 lbs.; 414 N || 20 cm./ .2 m || 47 sec. || 82.8 J || 82.8 J || 1.76 W || Christina || 96 lbs.; 428 N || 20 cm./ .2 m || 51 sec. || 85.6 J || 85.6 J || 1.68 W || Christina || 96 lbs.; 428 N || 20 cm./ .2 m || 62 sec. || 85.6 J || 85.6 J || 1.38 W || Sydney || 96 lbs.; 428 N || 20 cm./ .2 m || 39 sec. || 85.6 J || 85.6 J || 2.19 W || Sydney || 96 lbs.; 428 N || 20 cm./ .2 m || 48 sec. || 85.6 J || 85.6 J || 1.78 W || Claudia || 100 lbs.; 445 N. || 20 cm./ .2 m || 40 sec. || 89 J || 89 J || 2.23 W || Claudia || 100 lbs.; 445 N. || 20 cm./ .2 m || 52 sec. || 89 J || 89 J || 1.71 W || Aidan || 100 lbs.; 445 N. || 20 cm./ .2 m || 38 sec. || 89 J || 89 J || 2.34 W || Aidan || 100 lbs.; 445 N. || 20 cm./ .2 m || 42 sec. || 89 J || 89 J || 2.11 W || Lily || 100 lbs.; 445 N. || 20 cm./ .2 m || 44 sec. || 89 J || 89 J || 2.02 W || Lily || 100 lbs.; 445 N. || 20 cm./ .2 m || 49 sec. || 89 J || 89 J || 1.82 W || This experiment strengthened understanding of the nature of energy and how it is related to power. Energy is the ability to do work. Work equals force times distance, and power is work divided by time. Energy is needed to do work; however, variables of work and time impact how that energy is used.
 * Guiding Question One: //What is energy and what are the laws of energy and the transformation of energy?// **
 * What Do I Need to Know to Answer the Question? **
 * Power – the rate at which work is done; **formula – power = work divided by time;** measured in Watts
 * Work – work is force times distance; measured in Joules
 * Force – measured in newtons; 1 kg (kilogram) equals 9.8 N (newtons); 1 kg equals 2.2 pounds
 * Energy – the ability to do work
 * Forming a Hypothesis **
 * If work is force times distance, the greater the force and/or the greater the distance, the greater the work.
 * If power is work divided by time, then if the work remains constant, the greater the time the less the power, or the less the time the greater the power. Power and work are inversely proportionate to one another
 * Hypothesis **
 * If the work remains constant, the greater the time it takes, the less the power that is used; conversely, the less the time it takes, the greater the power. **
 * Testing the Hypothesis **
 * Note: Students provided their respective weights which were converted to Newtons with 1 kg equal to 1 N. Pounds were converted to kg with 1 kg equal to 2.2 pounds. Among all students, there were four different weights: 90 lbs., 93 lbs; 96 lbs., 100 lbs. Distance is measured in meters. **
 * Student || Weight || Height of Board || Time for 20 Reps || Work for 1 Rep || Work for 20 Reps || Power ||
 * Trial One
 * Trial Two
 * Trial One
 * Trial Two
 * Trial One
 * Trial Two
 * Trial One
 * Trial Two
 * Trial One
 * Trial Two
 * Trial One
 * Trial Two
 * Trial One
 * Trial Two
 * Trial One
 * Trial Two
 * Analyze and Conclude **
 * 1) The amount of work done during each trial remained the same because work equals force times distance, and neither the force nor the distance changed.
 * 2) The amount of power for trial one compared to trial two did change. The more time it took, the less the power. **Power changes as the time changes.**
 * 3) The students who weighed the same did the same amount of work. **Differing weights resulted in differing amounts of work as the distance remained the same.**
 * 4) Each student produced differing amounts of power as time varied among all of them. Power equals Work divided by Time. Even though the work may have been the same for students of the same weight, because they each completed the task in different amounts of time, the Power differed.
 * 5) A physical therapist could use music to change the power of output of her patients because we tend to move according to the beat we hear. The faster the music, the more inclined her patients would be to move faster in a task, producing more power.
 * Relating to the Guiding Question **


 * Plane-Mirror Images GQ2**
 * By: Christina, Lily and Clare**

How is an image produced by a plane mirror?
 * What is the question?**

You need to know what an image is and how the reflection of the light rays reflect off the mirror.
 * What do we need to know to answer the question?**
 * Hypothesis

1) What is an image?** An image is the reflection of an object, produced by light waves. You see a replica of the image one the other side of the mirror. It seems to be the same distance behind the mirror that the object is in front of the mirror. It is in a reverse position. It is facing the opposite was in the mirror. **Analyze and conclude** 4cm ** 4cm They are the same distance. They are the same degrees. Both of them are 30 degrees. They’re the same degrees. Both of them are 25 degrees. **Critical thinking and applications** If the incident ray enters from the left, then the reflected ray leaves to the right. If the incident ray enters from the right, then the reflected ray leaves to the left. The image and the object are both the same, but one is reversed. Yes, that would affect the image’s appearance; you’ll look different in the image. The image seems to be inside or behind the mirror because the light ray your brain thinks is going straight through the mirror is actually being reflected right back at you.
 * 2) When you look in a plane mirror, what size image do you see? How far away does the image appear to be?**
 * 1) At what distance is the object from the mirror line?
 * 2) At what distance is the image from the mirror line?**
 * 3) Compare the distance of the object and of the image from the mirror.**
 * 4) Compare the measures of the angle of incident and the angle of reflection for the rays from the left side of the paper.**
 * 5) Compare the measures of the angle of incidence and the angle of reflection for the rays from the right side of the paper.**
 * 1) Follow the path of an incident ray and its reflected ray. If the incident ray enters from the left, toward what direction does the reflected ray leave? If the incident ray enters from the right, toward what direction does the reflected ray leave?**
 * 2) Based on your to Question 1, how does the image compare with the object?**
 * 3) If the angle of incidence were not equal to the angle of reflection, would that affect the image’s appearance? Give a reason for your answer.**
 * 4) Why does the image seem to be inside or behind the mirror?**



** Making Waves GQ2 ** water plastic dropper metric ruler paper towel modeling clay cork or other small floating object ripple tank · ** What is a wave? ** A wave is a disturbance that transfers energy from place to place; a source of energy that causes a medium to vibrate. · ** What are the three types of waves? ** o ** Transverse- ** moves through the medium at an angle perpendicular to the direction in which the wave is traveling. o ** Longitudinal- ** moves medium parallel to the direction in which the wave is traveling. o ** Surface- ** a combination of transverse and longitudinal. · ** How do they interact with one another? ** o ** Reflections- ** wave does not pass through but reflects back. o ** Refraction- ** a wave bends as it passes through a medium. o ** Diffraction- ** wave passes a barrier or moves through a hole in a barrier. o ** Interference- ** when two waves meet, they impact each other: · constructive · destruction · ** What are the properties of a wave? ** o  ** Amplitude- ** the distance from rest position to highest point (crest) or lowest point (trough) o ** Frequency- ** the number of complete waves that pass in a given time measured in Hertz (Hz.) o ** Wave Length- ** the distance the wave travels before it starts to repeat. o ** Speed- ** speed= wave length x frequency
 * By: Susanne, Justin, Aidan, and James **
 * Problem: ** How do water waves interact with each other and with solid objects in their paths?
 * Materials: **
 * What do we need to know? **


 * Analyze and Conclude **
 * 1.) **** How are waves affected by the paper towel hanging in the water? ** The waves pushed the paper towel up and down along with the wave. It also made it move in the direction of the wave.
 * 2.) **** What happens when waves strike head on? When they strike it at an angle? ** When the waves strike the barrier straight on, they immediately bounced back into the center at the same time. When the waves strike at an angle, it bounced back to the center at different times. Then they bounced off each other to create a bigger wave.
 * 3.) **** What happens when waves strike a barrier with a gap in it? ** **With three gaps in it?** When there is a gap in the barrier, the waves go through the gap and then spread out. When there are three gaps in the barrier, the waves go through all three gaps and then spread out and they bounce off each other.
 * 4.) **** How does the behavior of waves in your model compare to the behavior of waves in a harbor? ** In a harbor, the waves are bigger which makes them have more momentum. Therefore, there is a bigger crash against a barrier.