" ""'" ' rum -..u. o n... gm 5 L L m w Lii 3:1\" 5 OGGQGQ E First, let's revisit string waves briefly as you encountered them in the first activity. 1. Recall, from part 1c, how the speed of a wave pulse depended on the amount of tension of the tension slider. Using the timer and ruler, estimate the speed (v = d/t} of a wave pulse for the lowest and highest available tensions, as well as for an intermediate value of tension. a. Speed with lowest tension: [3. Speed with intermediate {Center} tension: c. Speed with highest tension: d. Does the dependence (or order of the} of speeds make sense? Briefly comment: e. Calculate the speed ratio by dividing the fastest speed by the lowest speed: f. Now, calculate the ratio oftensions that you used from the ratio of speeds in part e above. 2. Now we're going to explore standing waves on strings and {by extension} in pipes. These represent a type of resonance pertinent to both musical instruments and speech and hearing. When oscillating, reflected waves can interfere with the outgoing wave and can create a standing wave composed of fixed nodes and antinodes if the frequency is just right. A node will always exist at each fixed end. Using the xed end setting, adjust the frequency, fine tuning it until maximum amplitude results for each standing wave mode (that is, m=1, m=2, etc.]. You can use the reference line feature to help you detect small changes in the amplitude as you fine tune the frequency. Note you may find it easier to find m=2 or 3 first (as in lecture), then go back to find m=1. Other Settings: amplitude: 0.05 cm tension: high damping: none Helpful hint: some green circles end up as nodes; watching these and ensuring that they appear stationary will allow you to fine tune the frequency and obtain a good estimate. Also, with there being no damping, there are always 'leftover waves' moving around so each time you adjust the frequency, restart the simulation to start fresh. b. Carefully tune and measure the frequency of the 4'\e. Predict the frequency of the 5th harmonic, m=5: (show calculation below) f. Set the frequency to what you predicted above. Watch for a minute to see if you need to fine tune to get a clearer 5th harmonic standing wave. How accurate does it seem, qualitatively? g. How accurate was your m=5 prediction, quantitatively? To assess this, estimate its % error: % Error = Theoretical Value - Experimental Value X 100 Theoretical Value