## Impulse (physics)

In classical mechanics , an **impulse** (abbreviated I or J ) is defined as the integral of a force with respect to time . When a force is applied to a rigid body it changes the momentum of that body. A small force applied for a long time can produce the same momentum change as a large force

**wikipedia.org**| 2011/8/19 2:08:40

## Mechanical impulse

In classical mechanics , an **impulse** is defined as the integral of a force with respect to time . When a force is applied to a rigid body it changes the momentum of that body. A small force applied for a long time can produce the same momentum change as a large force applied briefly, because

**wikipedia.org**| 2010/9/27 0:33:56

## Defining equation (physics)

In **physics** , defining equations are equations that define new quantities in terms of base quantities [ 1 ] . This article uses the current SI system of units , not natural or characteristic units . Contents 1 Treatment of vectors 2 Classical mechanics 2.1 Mass and inertia

**wikipedia.org**| 2011/10/5 16:01:22

## Elementary physics formulae

A list of elementary **physics** formulae commonly appearing in high-school and college introductory **physics** courses. The list consists primarily of formulas concerning mechanics , showing relations between matter , energy , motion , and force in Euclidean space , under the action of Newtonian

**wikipedia.org**| 2011/5/20 9:56:24

## Four-vector

velocity 2.2 Four-acceleration 2.3 Four-momentum 2.4 Four-force 3 Lorentz transformation 4 **Physics** of four-vectors 4.1 E = mc 2 4.2 E 2 = p 2 c 2 + m 2 c 4 5 Examples of four-vectors in electromagnetism 6 See also 7 References [ edit ] Mathematics of four-vectors

**wikipedia.org**| 2011/5/16 4:54:26

## Anti-gravity

Negative mass 1.4 Fifth force 1.5 General-relativistic "warp drives" 1.6 Breakthrough Propulsion **Physics** Program 2 Empirical claims and commercial efforts 2.1 Gyroscopic devices 2.2 Thomas Townsend Brown's gravitator 2.3 Gravitoelectric coupling 2.4 Recent progress 2.5

**wikipedia.org**| 2011/9/13 13:46:56

## Tachyon

A tachyon ( / ˈ t æ k i . ɒ n / ) is a hypothetical subatomic particle that moves faster than light . In the language of special relativity , a tachyon would be a particle with space-like four-momentum and imaginary proper time . A tachyon would be constrained to the space-like portion

**wikipedia.org**| 2011/10/3 8:01:16