A vibrator in a ripple tank vibrates with a frequency of 3.0 Hz and an amplitude of 2.5 cm. The resulting waves travel away from the source with a speed of 2.5 cm/s, passing under various markers floating on the water. (a)In what direction(s) do the marker move?
(b) With what frequency do the marker oscillate?
(c) If the frequency of the source is changed to 4.5 Hz, what will happen to: (i) the speed of the wave?
(ii) the frequency of the marker's oscillations?
(d) If the amplitude of the source is changed to 1.6 cm, what will happen to:
(i) the speed of the wave?
(ii) the frequency of the marker's oscillations?
To answer these questions, we need to understand the properties of waves and how they are affected by changes in frequency and amplitude.
(a) In a ripple tank, the waves move away from the source in all directions. Therefore, the markers will move in all directions as well, perpendicular to the direction of wave propagation.
(b) The frequency at which the marker oscillates can be determined by the frequency of the wave. In this case, the frequency of the wave is 3.0 Hz, so the markers will oscillate at the same frequency.
(c) (i) The speed of the wave depends on the medium through which it travels and is not directly affected by the frequency of the source. Therefore, changing the frequency to 4.5 Hz will not impact the speed of the wave.
(ii) The frequency of the marker's oscillations is determined by the frequency of the wave. Changing the frequency of the source to 4.5 Hz will result in an increase in the frequency at which the marker oscillates.
(d) (i) The speed of the wave is directly influenced by the amplitude of the source. As the amplitude increases, the speed of the wave also increases. Therefore, if the amplitude of the source is changed to 1.6 cm, the speed of the wave will increase.
(ii) The frequency of the marker's oscillations is not affected by changes in the amplitude of the source. It will remain the same as the frequency of the wave, which is determined by the frequency of the source.