Part 1: AssessmentOpportunity Waves andsound This is your first assessmentopportunity.There are four (4) tasks in this assessment.

Task 1: Wave characteristics

A standing transverse wave is formed in a string that is 5.0 m long. Both ends of the string are fixed. Eight loops are present in the standing wave. Answer the following questions about the wave. Make sure to show all work clearly.

1. Draw the standing wave. Label one node and one antinode. 2. Find the wavelength of the wave. Fully explain how you found the wavelength. 3. If it takes a wave 0.60 s to travel the length of the string, find the speed of the wave 4. Find the frequency of the wave.

Task 2: Speed of sound

Asaad, a grade 11 student, completed a lab activity to find the speed of sound in air using a closed-air column. The temperature of the room was measured to be 21 C. Using a tuning fork with a frequency of 1040 Hz, the following information was obtained about resonant lengths for the closed air column:

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Observations:

L1= 7.4 cm

L2= 22.5 cm

L3= 36.7 cm

Questions:

a) Use the resonant lengths to do three calculations to find the wavelength. Find the averag wavelength and use that in further calculations.

b) Using the wave equation, what is the speed of sound in the air column? c) What is the theoretical speed of sound in the room according to the temperature?

Task 3: Application of thedopplereffect

a) Write a paragraph explaining what the Doppler Effect is and the different effects it has on the observed frequency when the source of the sound is moving toward an observer ver- sus when it is moving away from an observer. Then, state two ways in which the Doppler Effect is applied to situations in everyday life. You will need to do independent research to fin the applications.

b) A train on a straight track sounds a 400 Hz horn when passing a parked car on the road. The train is moving at 20 m/s and the temperature is 10C. Find the apparent frequency of the horn for a person sitting inside the car when the train is approaching and when the train is moving away.

Task 4: Reflection ofsoundwaves

A boat is floating at rest in dense fog near a large cli f. The captain sounds a horn at water level and the sound travels through the salt water (1470 m/s) and the air (340 m/s) simultaneously. The echo in the water (due to the cliff) takes 0.40 s to return. How much additional time will it take for the echo in the air to return?

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