Mediaspace scheduled maintenance: Aug 25, 2026 07:00 - 12:00 AM. During this time, videos will be temporarily unavailable. Check status updates.

Lecture

Dimensional Analysis: Gravitational Constant

Description

This lecture focuses on correcting exercise 3 of series 1, which deals with dimensional analysis, a useful tool in physics. The instructor explains the importance of dimensions and units in physical quantities, using the gravitational constant G as an example. Through isolating G in the equation for gravitational force, the dimensional analysis is performed step by step, highlighting the dimensions and units involved. The lecture concludes with a reminder to be cautious with the distinction between dimensions and units, emphasizing the significance of correctly interpreting symbols in physics.

In MOOC

Warm-up for EPFL

Official source

Ontological neighbourhood

Physics

Relativity: General relativity

Related concepts (32)

Gravitational constant

The gravitational constant (also known as the universal gravitational constant, the Newtonian constant of gravitation, or the Cavendish gravitational constant), denoted by the capital letter G, is an empirical physical constant involved in the calculation of gravitational effects in Sir Isaac Newton's law of universal gravitation and in Albert Einstein's theory of general relativity. In Newton's law, it is the proportionality constant connecting the gravitational force between two bodies with the product of their masses and the inverse square of their distance.

Force

In physics, a force is an influence that can cause an object to change its velocity, i.e., to accelerate, unless counterbalanced by other forces. The concept of force makes the everyday notion of pushing or pulling mathematically precise. Because the magnitude and direction of a force are both important, force is a vector quantity. It is measured in the SI unit of newton (N) and often represented by the symbol F.

Gravitational wave

Gravitational waves are waves of the intensity of gravity that are generated by the accelerated masses of an orbital binary system, and propagate as waves outward from their source at the speed of light. They were first proposed by Oliver Heaviside in 1893 and then later by Henri Poincaré in 1905 as waves similar to electromagnetic waves but the gravitational equivalent. Gravitational waves were later predicted in 1916 by Albert Einstein on the basis of his general theory of relativity as ripples in spacetime.

Gravitational energy

Gravitational energy or gravitational potential energy is the potential energy a massive object has in relation to another massive object due to gravity. It is the potential energy associated with the gravitational field, which is released (converted into kinetic energy) when the objects fall towards each other. Gravitational potential energy increases when two objects are brought further apart. For two pairwise interacting point particles, the gravitational potential energy is given by where and are the masses of the two particles, is the distance between them, and is the gravitational constant.

Gravitational field

In physics, a gravitational field is a model used to explain the influences that a massive body extends into the space around itself, producing a force on another massive body. Thus, a gravitational field is used to explain gravitational phenomena, and is measured in newtons per kilogram (N/kg). Equivalently, it is measured in meters per second squared (m/s2). In its original concept, gravity was a force between point masses.

Related lectures (45)

Static Isotropic Metric

Explores static isotropic metric properties and equations in physics, focusing on the behavior outside the gravitational field.

Gravitational Field Equations

Covers the formulation of gravitational field equations and the motion of particles in gravitational fields.

Special and General Relativity

Introduces special and general relativity, Einstein equations, and gravitational dynamics.

Energy and Work: Fundamentals

Introduces the fundamentals of energy, work, and power, covering harmonic oscillators, conservative forces, and energy conservation.

Cosmological Puzzles: Dark Matter and Energy