Mod 7 Trial Q (1 Viewer)

[krypticlemonjuice]

Can someone please explain how B is achieved for this question?

 

[howcanibesmarter]

Okay so lets first define path difference - its the difference in the path by the two waves.

So PQR travels a total of 38m, while PR only travels 30. So whats the path difference? Its 8m

Now we are given frequency, and using c=fλ we can find wavelength. Plugging into the calculator gives you 4.

So what is the path difference in terms of wavelength λ? Its simply 8m (the path difference) divided by the wavelength given which is 4.

This gives you 8/4 = 2 Therefore answer is B

 

[krypticlemonjuice]

Okay so lets first define path difference - its the difference in the path by the two waves.

So PQR travels a total of 38m, while PR only travels 30. So whats the path difference? Its 8m

Now we are given frequency, and using c=fλ we can find wavelength. Plugging into the calculator gives you 4.

So what is the path difference in terms of wavelength λ? Its simply 8m (the path difference) divided by the wavelength given which is 4.

This gives you 8/4 = 2 Therefore answer is B

Thank you so much!