Wavelength of ultrasonic waves of frequency 100 kHz at NTP is

Options

A. 0.33 m
B. 3.3 cm
C. 0.33 cm
D. 0.033 cm

Explanation

To find the wavelength of ultrasonic waves of frequency 100 kHz at NTP (Normal Temperature and Pressure), we can follow these steps:

### Step-by-Step Solution:

1. **Identify the given values**:
- Frequency (f) = 100 kHz = 100,000 Hz (since 1 kHz = 1,000 Hz)
- Speed of sound at NTP (v) = 330 m/s

2. **Use the formula for wavelength**:
The relationship between wavelength (λ), speed of sound (v), and frequency (f) is given by the formula:
\[ \lambda = \frac{v}{f} \]

3. **Substitute the values into the formula**:
\[ \lambda = \frac{330 \, \text{m/s}}{100,000 \, \text{Hz}} \]

4. **Calculate the wavelength**:
\[ \lambda = \frac{330}{100,000} = 0.0033 \, \text{m} \]

5. **Convert the wavelength from meters to centimeters**:
Since 1 meter = 100 centimeters, we convert:
\[ \lambda = 0.0033 \, \text{m} \times 100 = 0.33 \, \text{cm} \]

6. **Final answer**:
The wavelength of ultrasonic waves of frequency 100 kHz at NTP is **0.33 cm**.