Question

In microwave oven, we use electromagnetic oscillators which produce electromagnetic waves in the wavelength range (A) $1\mathrm{mm}$ to $10\mathrm{m}$ (B) $0.7\mu \mathrm{m}$ to $1\mathrm{mm}$ (C) $0.1\mathrm{m}$ to $1\mathrm{mm}$ (D) $0.1\mu \mathrm{m}$ to $0.7\mu \mathrm{m}$

Short answer

The correct range of wavelengths for the electromagnetic oscillations in a microwave oven is (C) $0.1\mathrm{m}$ to $1\mathrm{mm}$, as it covers a significant portion of the microwave range while other options cover either a different range or only a small portion of the microwave range.

Step-by-step solution

Identify the microwave range

First, let's identify the range of wavelengths that belongs to the microwave category of the electromagnetic spectrum. Microwaves fall within the range of $1\mathrm{mm}$ to $100\mathrm{cm}$ wavelengths.

Compare the given options to the microwave range

Now, let's analyze the given options and compare them to the identified microwave range we found in Step 1. (A) $1\mathrm{mm}$ to $10\mathrm{m}$ - This option starts in the microwave range, but it extends further out into the radio wave spectrum. (B) $0.7\mu \mathrm{m}$ to $1\mathrm{mm}$ - This option starts in the infrared range and ends with the starting point of the microwave range. So, it doesn't cover the entire microwave range. (C) $0.1\mathrm{m}$ to $1\mathrm{mm}$ - This option covers the range from $10\mathrm{cm}$ to $1\mathrm{mm}$, which is part of the microwave range. (D) $0.1\mu \mathrm{m}$ to $0.7\mu \mathrm{m}$ - This option corresponds to the ultraviolet part of the electromagnetic spectrum, not the microwave range.

Choose the correct option

Based on our analysis in Step 2, the best answer is option (C) $0.1\mathrm{m}$ to $1\mathrm{mm}$, as it covers a significant portion of the microwave range, while the other options cover either a different range or only a small portion of the microwave range.

Key concepts

Electromagnetic Spectrum

The electromagnetic spectrum is a range of all types of electromagnetic radiation. These are waves of energy that travel through space at the speed of light. Visible light, which lets us see the world, is just one small part of this wide spectrum.
Within this spectrum, different types of radiation include:

• Gamma rays
• X-rays
• Ultraviolet light
• Visible light
• Infrared radiation
• Microwaves
• Radio waves

Each type of radiation has a different wavelength, ranging from very short (like gamma rays) to very long (like radio waves). This diversity in wavelength allows electromagnetic waves to be useful for a variety of purposes. For example, visible light enables sight, while microwaves are used for heating in microwave ovens. Understanding where microwaves fit within this spectrum helps us grasp their unique properties.

Microwaves

Microwaves are a type of electromagnetic radiation, characterized by their medium-length wavelengths. They are longer than infrared light but shorter than radio waves. Microwaves are particularly unique due to their ability to heat water molecules, which is why they're used in microwave ovens. When absorbed by water, microwaves cause the molecules to vibrate, producing heat.
Common uses of microwaves include:

• Cooking and heating food in microwave ovens
• Wireless communication, like Wi-Fi and Bluetooth
• Radar technology

In the electromagnetic spectrum, microwaves have wavelengths ranging from about 1 millimeter to 1 meter. This range allows them to penetrate common types of materials, like glass and plastic, without much interference, making them practical for various technologies.

Wavelengths

Wavelengths are a fundamental property of waves, including electromagnetic waves. They are measured as the distance between two consecutive peaks of a wave. The length of a wave determines its properties and, in the case of electromagnetic waves, its type within the electromagnetic spectrum.
The wavelength range for microwaves is typically between 1 millimeter (0.001 meter) and 1 meter (100 centimeters). This specific range is what distinguishes microwaves from other electromagnetic waves, like radio waves and infrared. Understanding wavelength is crucial as it affects how waves interact with materials and objects.

• Shorter wavelengths, like X-rays, can pass through soft tissue, making them useful for medical imaging.
• Longer wavelengths, like radio waves, can travel long distances and through various barriers, making them ideal for communication.

So, knowing the wavelength of a wave helps scientists and engineers design technologies that leverage these unique characteristics.