Hectometer
A hectometer (hm) is a unit of length in the metric system, equal to 100 meters. It is larger than a meter but smaller than a kilometer. While it is part of the official metric system, the hectometer is rarely used in daily life or science. For example, a running track is 400 meters long, which is 4 hectometers. The symbol for hectometer is "hm". Although not commonly seen, it can be useful for measuring medium-range distances, especially when kilometers feel too large and meters too small.
Planck Length
The Planck length is the smallest meaningful unit of length in physics, representing a fundamental scale at which classical ideas about gravity and space-time break down and quantum effects dominate.
It is defined as approximately 1.616 × 10⁻³⁵ meters.
The Planck length is derived from fundamental constants: the speed of light, Planck’s constant, and the gravitational constant.
It sets a theoretical limit below which the very concepts of space and distance may lose conventional meaning.
Used mainly in theories of quantum gravity and string theory.
Key facts:
1 Planck length ≈ 1.616 × 10⁻³⁵ m
Smallest scale in quantum physics and cosmology
Represents a scale where quantum effects of gravity become significant
The Planck length is crucial for understanding the fabric of the universe at its most fundamental level.
No conversions available for length.