Question 7 (2 points) A sound wave of frequency 450 Hz is emitted from A and travels towards B, a distance of 150 m away. Take the speed of sound to be 341 m/s. How many wavelengths fit in the distance from A to B? [Click on in your answer box to use more math tools]Question 8 (1 point) The noise of thunder is heard 3 s after the flash of lightning. How far away is the place where lightning stuck? (Take the speed of sound to be 340 m/s.) [Click on [x] in your answer box to use more math tools]Question 9 (2 points) A transverse wave travels in medium X with a speed of 800 m/s and a wavelength of 4 m. The wave then moves into medium Y, traveling with a speed of 1600 m/s. a. Determine the frequency of the wave in medium Y. (1 mark) b. Determine the wavelength of the wave in medium Y. (1 mark) [Click on in your answer box to use more math tools]Question 10 (2 points) Water wave crests in a lake are 5.0 m apart and pass by an anchored boat every 2.0 s. What is the speed of the water waves? [Click on in your answer box to use more math tools]Question 11 (7 points) Students are attempting to determine the speed of sound in air using tuning forks and tubes which are closed at one end. In this procedure, the tube is filled with water, and a tuning fork of known frequency is struck. The vibrating tuning fork is then held over the tube filled with water, and the water is slowly drained out of the tube while students listen for the loudest possible sound at the first resonant condition. Once the loudest possible sound is heard (the first harmonic), the distance from th e top of the tube to the water's surface () is measured and recorded. This procedure is repeated for six tuning forks of varying frequencies. Data is recorded in the table below. Trial 1 2 3 4 5 Freq. 128 256 288 384 426.6 512 (Hz Period (s) 1 (m) 0.65 0.33 0.29 0.23 0.19 0.17 1 (m) a. Write an equation for the wavelength of the sound wave ( ) ) as a function of L. (1 mark) b. Use the empty boxes in the data table to record the calculated values for periods and wavelengths. (2 marks) c. Plot a linear graph of wavelength () ) as a function of period (7) on your graphing calculator (For example, TI-83+) and calculate a best-fit line. What is the slope of your best-fit line? (3 marks). d. Using your best-fit line to determine the speed of the sound waves in air. (1 mark)