What is the frequency of a wave if 3 crests pass in 6 seconds?
a. 0.5 hz
b. 2 hz
c. 9 hz
d. 18 hz

b. 2Hz

Explanation:

Frequency is defined as the number of wavelengths passing a particular point per second.

If 3 crests pass a point in two seconds, then we know that 6 crests pass the point per second.

Therefore 2 wavelengths pass the point per second, and hence the frequency of the wave is 2Hz.

when heated, the valance electrons increased their speed and transferred the heat from electron to electron.   i just took the test.

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