Question

a machine produces compression waves in a spring that is 120 cm long by pulsing twice every second. the back and forth movement of the pulse creates compressed sections of the spring that are 30 cm apart and travel toward the other end of the spring
which property of the wave does the value of two per second describe?
a. amplitude
b. wavelength
c. intensity
d. frequency

Explanation:

• Amplitude refers to the maximum displacement of a wave from its equilibrium position, which is not related to the rate of pulsing.
• Wavelength is the distance between identical points on consecutive waves (given as 30 cm here), not the pulsing rate.
• Intensity describes the power per unit area carried by a wave, which is not measured in pulses per second.
• Frequency is defined as the number of wave cycles (or pulses, in this case) that occur per unit time, which matches the "twice every second" description.

Answer:

D. frequency