Question

The distance between four consecutive crests of wave is 120 cm. If the waves are produced at the rate of 240 per minute, calculate (i) wavelength (ii) time period (iii) wave velocity​

Answer 1

Answer :

The distance between four consecutive crests of wave (3λ) = 120 cm.

Waves are produced at the rate of 240 per minute.

We have to find ;

• Wavelength
• Time period
• Wave velocity

★ The distance between two consecutive crests of wave is called wavelength (λ).

➠ 3λ = 120

➠ λ = 120/3

➠ λ = 40 cm ___ (I)

We have given data of frequency that the waves are produced at the rate of 240 per minute$.$

Waves produced per second :

• 240/60 = 4

∴ Frequency = 4 Hz

We know that, time period is the reciprocal of frequency.

➠ T = 1 / n

➠ T = 1 / 4

➠ T = 0.25 s ___ (II)

Wave velocity is given by : v = λ/T

➠ v = 40/0.25

➠ v = 40 × 100/25

➠ v = 160 cm/s ___ (III)