Coefficient of static friction

The coefficient of static friction, for two materials is the constant of proportionality between the normal force and the maximum force of static friction. It is always a number between zero and one.

Collision

When objects collide, each object feels a force for a short amount of time. This force imparts an impulse, or changes the momentum of each of the colliding objects. The momentum of a system is conserved in all kinds of collisions. Kinetic energy is conserved in elastic collisions, but not in inelastic collisions. In a perfectly inelastic collision, the colliding objects stick together after they collide.

Completely inelastic collision

A collision in which the colliding particles stick together.                                                                                                        

Conduction

Heat transfer by molecular collisions.

Conservation of Angular Momentum

If the net torque acting on a rigid body is zero, then the angular momentum of the body is constant or conserved.

Conservation of momentum

The principle stating that for any isolated system, linear momentum is constant with time.

Cross product

A form of vector multiplication, where two vectors are multiplied to produce a third vector. The cross product of two vectors, A and B, separated by an angle, , is , where is a unit vector perpendicular to both A and B. To deine which direction points, you must use the right-hand rule.

Displacement

A vector quantity, commonly denoted by the vector s, which reflects an object’s change in spatial position. The displacement vector points from the object’s starting position to the object’s current position in space. If an object is moved from point A to point B in space along path AB, the magnitude of the object’s displacement is the separation of points A and B. Note that the path an object takes to get from point A to point B does not figure when deining displacement.

Distance

A scalar quantity. If an object is moved from point A to point B in space along path AB, the distance that the object has traveled is the length of the path AB. Distance is to be contrasted with displacement, which is simply a measure of the distance between points A and B, and doesn’t take into account the path followed between A and B.

Efficiency

For a heat engine, the ratio of work done by the engine to heat intake. Efficiency is never 100%.

Elastic collision

A collision in which both kinetic energy and momentum are conserved.

Electric generator

A device that converts mechanical energy to electrical energy by rotating a coil in a magnetic field; sometimes called a “dynamo.”

Electromagnetic wave

A transverse traveling wave created by the oscillations of an electric field and a magnetic field. Electromagnetic waves travel at the speed of light, m/s. Examples include microwaves, X rays, and visible light.

Electron

A negatively charged particle that orbits the nucleus of the atom.

Energy

A conserved scalar quantity associated with the state or condition of an object or system of objects. We can roughly define energy as the capacity for an object or system to do work. There are many different types of energy, such as kinetic energy, potential energy, thermal energy, chemical energy, mechanical energy, and electrical energy.

Equilibrium

The state of a nonrotating object upon whom the net torque acting is zero.

Equilibrium position

The stable position of a system where the net force acting on the object is zero.

Faraday’s Law

A law, | | = , which states that the induced emf is the change in magnetic flux in a certain time.

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