Question

What is the ratio of wavelengths between P, Q and R?

Options

• 3 : 2 : 1

• 1 : 2 : 3

• 6 : 3 : 2

• 2 : 3 : 6

Answer 1

6 : 3 : 2

Explanation:

The string patterns have one, two and three loops for P, Q and R. For the same string length, wavelength decreases as the number of loops increases, giving the ratio $$2L : L : \frac{2L}{3} = 6 : 3 : 2$$.