Science

Electromagnetic Spectrum

A range of all types of electromagnetic waves arranged by wavelength or frequency.

Visible Spectrum

Part of the EM spectrum visible to the human eye, ranging from approximately 380 nm (violet) to 750 nm (red).

VIBGYOR

A mnemonic for the colors in the visible spectrum: Violet, Indigo, Blue, Green, Yellow, Orange, Red.

Energy and Frequency Relationship

Energy is directly proportional to frequency; higher frequency = higher energy.

Wavelength and Energy Relationship

Wavelength is inversely proportional to energy; longer wavelength = lower energy.

Planck's Constant

A constant (h) used in the formula E=hf, representing the relationship between energy and frequency.

Speed of Light Formula

c = λf, where c is the speed of light, λ is wavelength, and f is frequency.

Radio Waves

Part of the electromagnetic spectrum used primarily for communication (e.g., TV, radio).

Microwaves

Electromagnetic waves used for cooking and satellite communication.

Infrared Radiation

Electromagnetic waves used in remote controls and thermal imaging.

Ultraviolet (UV) Radiation

High-energy electromagnetic waves used for sterilization and tanning.

X-rays

High-energy waves used mainly for medical imaging.

Gamma Rays

The highest energy electromagnetic waves used for cancer treatment and sterilizing medical equipment.

Non-Ionizing Radiation

Low energy radiation that does not ionize atoms (e.g., radio waves, microwaves).

Ionizing Radiation

High energy radiation that can ionize atoms and damage DNA (e.g., UV rays, X-rays).

ELF Radio Waves

Extremely low-frequency radio waves best suited for underwater communication.

Reflection

Bouncing back of light when it hits a surface.

Specular Reflection

Reflection from smooth surfaces, such as mirrors.

Diffuse Reflection

Reflection from rough surfaces, such as walls.

Concave Mirror

A mirror that curves inward and focuses light.

Convex Mirror

A mirror that curves outward and diverges light.

Principal Rays in Concave Mirrors

Four rays used to analyze image formation: Parallel Ray, Focal Ray, Center Ray, and Vertex Ray.

Parallel Ray (PF)

A ray of light that is parallel to the principal axis and reflects through the focal point.

Focal Ray (FP)

A ray that passes through the focal point and reflects parallel to the principal axis.

Center Ray (CC)

A ray that passes through the center of curvature and reflects back on itself.

Vertex Ray (V)

A ray that hits the vertex and reflects symmetrically.