Which of the following statements is correct?

Options

A. Ultrasonic waves can travel in vacuum.
B. Wavelength of ultrasonic waves of the same order as that of microwaves.
C. Frequency of ultrasonic waves is of the same order as that of x-rays.
D. speed of ultrasonic waves is of the same order as that of light.

Explanation

To determine which of the statements regarding ultrasonic waves and microwaves is correct, we will analyze each statement step by step.

### Step 1: Analyze the first statement
**Statement:** "Ultrasound and ultrasonic waves can travel in vacuum."

**Explanation:** Ultrasonic waves are mechanical waves, which means they require a medium (like air, water, or solids) to travel. They cannot travel in a vacuum because there are no molecules to transmit the sound. Therefore, this statement is **incorrect**.

### Step 2: Analyze the second statement
**Statement:** "Wavelength of ultrasonic waves is of the same order as that of microwave."

**Explanation:** Ultrasonic waves and microwaves are both types of waves, but they operate at different frequencies and wavelengths. The wavelength of ultrasonic waves is typically much shorter than that of microwaves. Thus, this statement is **incorrect**.

### Step 3: Analyze the third statement
**Statement:** "Frequency of ultrasonic wave is of the same order as that of microwave."

**Explanation:** The frequency of ultrasonic waves is generally much higher than that of microwaves. Ultrasonic waves typically have frequencies above 20 kHz, while microwaves operate in the range of gigahertz (GHz). Therefore, this statement is **incorrect**.

### Step 4: Analyze the fourth statement
**Statement:** "Speed of ultrasonic wave is of the same order as that of light."

**Explanation:** The speed of ultrasonic waves in a medium (like air or water) is significantly lower than the speed of light in a vacuum. The speed of sound (ultrasonic waves) is about \(3 \times 10^2\) m/s, while the speed of light is approximately \(3 \times 10^8\) m/s. Therefore, this statement is **incorrect**.

### Conclusion
After analyzing all the statements, we find that all four statements are incorrect. Therefore, none of the statements provided is correct.