S2

Sketch the resultant wave when the two traveling wave pulses in the figure interact, specifically when point A on the left wave is at the same position as point B on the right wave. Identify areas as constructive or destructive interference.

In a two-point source interference pattern in a ripple tank, a point is one wavelength farther from one sourcethan the other. If the two sources are in phase, then there isa. destructive interference at this pointb. constructive interference at this pointc. both constructive and destructive interference simultaneouslyd. neither constructive nor destructive interference at this pointe. no interaction between the two waves at this point

Below is a figure representing two sources releasing sound waves. a. Label 1 point of constructive interference, and explain why this this point represents constructive interference.  b. Label 1 point of destructive interference, and explain why this point represents destructive interference.

The figure below shows two waves that occupy the same point in space. Copy the sketch into a sheet of paper using the dimensions indicated. Draw the wave that results from the interference of these two waves.

Draw a figure to show the resultant wave produced when two coherent waves (with equal amplitudes x) interact in phase. What is the amplitude of the resultant wave? If the phase difference between the coherent waves is changed to 60º, what will be new amplitude?

2. Consider the following diagram showing the crossing of two individual wave packets. Which phases represent total constructive interference? Which phases represent total destructive interference? a. Imagine that these two waves are water waves. If you were observing these waves on a pond, what would the water look like in phase E? What about in phase G? (Hint: Think about the sum of the two waves, and sketch what that sum would look like. Ask yourself, are the waves adding together, or canceling each other out?) b. Now imagine these two waves are light waves. In which phases would the interfering light waves appear brightest? In which phases would they appear the dimmest? A B C D E F G Figure 1: Crossing of two individual wave packets.

Solve within 20 minutes and give correct answer.

Two identical sources of sound separated by 2 m generate waves that are in phase with each other. The diagram shows a snapshot in time of the waves from the two sources, where the lines denote successive crests of the waves (solid lines from one and dashed lines from the other). 11 What is the wavelength λ of the waves? Provide a numerical answer. Draw the line on the diagram where the path difference of the waves from the two sources is always zero. Is the interference on this line constructive or destructive? Is this a nodal or an antinodal line? Mark points on the diagram where the path lengths from the two sources differ by X/2, X, 3A/2, and 2A. Join the points to draw all the possible nodal and antinodal lines. If you walk around the two sources in a large circle with 5 m radius from the midpoint of the two sources, at how many places will you experience complete sound cancellation?

Options for question 1: A, B, C Options for question 2 and 3:  1/2, 1/4, 1, 2, or 4