Exploration 3: A Moving Source at Different Velocities

Question

Procedure
1. Set Wave speed to 10.0 cm/s and Source frequency to 1.0 Hz. Place the detector anywhere.
2. Set Source speed to 6.0 cm/s.
Select Go. Sketch the resulting wave-front pattern on a separate sheet of paper.
3. Select Go. Sketch the resulting wave-front pattern on the separate sheet of paper.
4. Set Source speed to 8.0 cm/s.
5.Select Go. Sketch the resulting wave-front pattern on the separate sheet of paper.
6. Repeat steps 4 and 5 for 10.0 cm/s, 12.0 cm/s, and 14.0 cm/s source speeds.
Observation and Analysis
1. What happens to the wave-front pattern as the source speed is increased to equal the wave speed?
2. What happens to the wave-front pattern as the source speed is increased beyond the wave speed?
Conclusions
Describe how the motion and frequency of a wave source affect the waves that source produces.
Inquiry Extension
Luisa is swinging on a playground swing at school. A teacher facing her blows a whistle to let the children know recess is over. As Luisa swings, what does she hear? When does she hear the highest pitch?