Q108 / 150 · MHT CET 2026 (18 April Shift 1) · Physics
The number of waves counted by an observer on the sea-coast in one minute is 54. If the wavelength of the waves is $5\ \text{m}$ then the velocity of the waves in $\text{m/s}$ will be
- Correct answerA$4.5$
- B$5.4$
- C$6.3$
- D$7.2$
Solution
Frequency of the waves is given by the number of waves passing per second.
$f = \dfrac{54}{60} = 0.9\ \text{Hz}$
Wavelength of the waves, $\lambda = 5\ \text{m}$
Velocity of the waves, $v = f \lambda$
$v = 0.9 \times 5 = 4.5\ \text{m/s}$
Answer: $4.5$
$f = \dfrac{54}{60} = 0.9\ \text{Hz}$
Wavelength of the waves, $\lambda = 5\ \text{m}$
Velocity of the waves, $v = f \lambda$
$v = 0.9 \times 5 = 4.5\ \text{m/s}$
Answer: $4.5$
Hence, the correct answer is option: 'A'.