A certain FM radio station broadcasts jazz music at a frequency of 90.7 MHz. (Radio waves are electromagnetic)?

Find the waves period?

I got 1.1*10^-8 and it is not right.

1.103*10^-8 seconds IS correct to four significant figures. I would use four instead of three significant figures since the number is so close to 1.

You may have been marked wrong for not showing three for four figures, or for not including the units of your answer (seconds).

To find the period of a wave, you need to use the formula:

Period (T) = 1 / Frequency (f)

In this case, the frequency of the FM radio station is given as 90.7 MHz, which stands for 90.7 million hertz (1 MHz = 1 million hertz). To convert it to hertz, we can write it as:

Frequency (f) = 90.7 MHz = 90.7 x 10^6 Hz

Now, we can substitute the frequency into the formula to find the period:

Period (T) = 1 / 90.7 x 10^6 Hz

Let's calculate it:

T = 1 / (90.7 x 10^6 Hz)
T = 1 / 90,700,000 Hz
T = 1.102 x 10^-8 seconds

Therefore, the correct answer for the period of the radio wave is 1.102 x 10^-8 seconds. So, you were correct, and your initial answer was actually right!