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Introductory Physics Hunter CollegeWaves on A String a wave travels down a cord—say, from left to right—the particles of the cord vibrate back and forth in a direction transverse (that is, perpendicular) to the motion of the wave itself. Such a wave is called a transverse wave. There exists another type of wave known as a longitudinal wave. In a longitudinal wave, the vibration of the particles of the medium is along the direction of the wave’s motion. Longitudinal waves are readily formed on a stretched spring or Slinky by alternately compressing and expanding one end.Procedure – Part One: Variables Affecting the Speed of a WaveThe speed of a wave depends on the properties of the medium in which it travels. The speed of a transverse wave on a stretched string or cord, for example, depends on the tension in the cord, FT , and on the mass per unit length of the cord, μ. If μ is the mass of a length l of wire, μ = m/l. For waves of small amplitude, the wave speed is The wave speed, v, is the speed at which wave crests (or any other fixed point on the wave shape) move forward. A wave crest travels a distance of one wavelength, λ, in a time equal to one period, T. Thus the wave speed is v = λ/ T. Then, since 1/T = f,v = λ f.Prelab1. Explain what are wave amplitude, frequency, wavelength, period, and speed?2. Give one example for each?including unit.1, Open the simulation called ‘Wave on a String’, found here. Navigate to the “Lab’ tab.Observe the Properties of the Wave:Properties of wave on a stretched string: To study the wave Properties under the influence of different conditions. Know your interface. Open the simulator -> go to Manual -> Wiggle the left end of the string and watch the wave propagation.Click on pulse and check how pulse is generated. Click on oscillate to watch the oscillation. Scroll the damping and tension scroll bars to get an idea how the oscillation varies with increasing damping and tension. You already have idea of amplitude, time period and frequency of oscillation. Check on the Ruler and Timer boxes to use ruler and stopwatch. You can get a rough estimation how the amplitude and frequency vary with increase in damping and tension. Remember, the tension slider does not behave linearly — it operates on powers of two (High is 4x larger than Low). Change the conditions by clicking on the boxes at your right and try Fixed End, Loose End and No End to get an idea how the wave behaves under these conditions. Describe motion of each green bead.Is this a transverse or longitudinal wave? In which direction is the wave traveling compared to the disturbance, perpendicular or parallel?Do waves transfer matter? Change one variable each time from the Base trial for the speed of wave by measuring distance and time. Use No End and Slow Motion.TrialAmplitude(A)Frequency (F)Wavelength (λ)Tension (T)Damping(D)SpeedDistance/TimeBase trial1 cm1.5 Hz2.5 cmMediumNone7.5cm/2s=3.75 cm/sChange AChange FMaximize TMinimize TInsert screenshots for each trialWhat conclusions that you can make based on this experiment?Is v = λ x f the same as the measured speed?Procedure – Part Two: Reflection (Insert screenshots for each experiment)Set No Damping and Medium Tension. Select Fixed End and send a Pulse. Observe and describe the reflection on both ends. Change to Oscillation. Observe and describe the reflection on both ends. You should also describe what happen when two waves meet.Select Loose End and send a Pulse. Observe and describe the reflection on both ends.Change to Oscillation. Observe and describe the reflection on both ends. You should also describe what happen when two waves pare the waves of oscillation between the Loose End and the Fixed End.Procedure – Part Three: Standing Wave Set the Tension in the middle, no Damping, and Fixed End. Based on previous calculation, calculate, and find out the fundamental frequency (n=1) of standing wave. Describe and explain the simulation. Insert the screenshot here.Find out n=2 and 3 standing waves. Insert the screenshots here. ................
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