The diagram above illustrates a mode of vibration of a wire of length 125 cm. The speed of the waves along the wire is 120 ms-1. Use the diagram to answer questions 2 and 3.
 

The diagram above illustrates a mode of vibration of a wire of length 125 cm. The speed of the waves along the wire is 120 ms-1. Use the diagram to answer questions 2 and 3.
 

A.

1.00m

B.

0.75m

C.

0.25m

D.

0.50m

Correct answer is D

Number of cycles, n = \(2\frac{1}{2} = \frac{5}{2}\)

Length = nλ

λ = \(\frac{Length}{n}\)  =  \(\frac{125}{\frac{5}{2}}\)

Therefore, λ = 50cm = 0.50m.