Question

A wave pulse travels along a horizontal string. As the pulse passes a pint on the string, the point moves vertically up and then back down again. How does the vertical speed of the point compare to the speed of the wave?

• the speed of the point equals the speed multiplied by the wavelength and divided by the string's length.
• the wave speed equals the point speed multiplies by the wavelength and divided by the string's length.
• the speed of the point is 2 times greater than the wave speed.
• the speed of the point could be neglected compared to the wave speed.
• the wave speed could be neglected compared to the speed of the point.
• the speeds could not be uniquely compared, because there is no fixed relationship between them.

Answer 1

The vertical speed of the point is not directly related to the wavelength, but rather to the amplitude of the wave. Therefore, none of the options given are correct.

However, we can say that the vertical speed of the point depends on the frequency of the wave and the amplitude of the wave. The higher the frequency and/or amplitude of the wave, the greater the vertical speed of the point.

On the other hand, the speed of the wave is determined by the properties of the string, such as its tension and mass density. Therefore, the speeds of the point and the wave are not directly related, and cannot be compared in a fixed way.