Question #9d941

1 Answer
Mar 29, 2016

#"A"#

Explanation:

In simple terms, frequency tells you how many repeating cycles you get per unit of time.

#color(blue)(|bar(ul(color(white)(a/a)"frequency" = "no. of cycles"/"unit of time"color(white)(a/a)|)))#

In your case, a repeating cycle will be the period of the wave, i.e. the time needed for a single cycle to occur.

http://www.physics.usyd.edu.au/teach_res/mp/doc/wm_string_1.htm

You're dealing with four waves of different periods, and implicitly of different frequencies.

The #x#-axis of the graphs represents time. Notice that all four graphs use the same interval for the #x#-axis, which means that the frequency of the waves will depend exclusively on how many periods can fit along the #x#-axis.

More specifically, if you get more periods into the same period of time, you will get a higher frequency.

Notice that in order to fit more periods into the same time frame, you need to have shorter periods. This gives you the relationship that exists between frequency and period

#color(blue)(|bar(ul(color(white)(a/a)"frequency" = 1/"period"color(white)(a/a)|)))#

So, the shorter the period, the more periods you can get in the same time frame.

The more periods you can get in the time frame, the higher the frequency.

https://commons.wikimedia.org

This means that graph #"A"# will describe the wave with the highest frequency.

By comparison, graph #"B"# will describe the wave with the lowest frequency, since it contains the fewest periods in the given time frame.

In fact, you can arrange these graphs in order of decreasing frequency

#"A" > "D" > "C" > "B"#