4a._work_energy_power (1).pdf

Energy

The capacity to do work or produce change, existing in various forms such as kinetic, potential, thermal, and more.

Law of Conservation of Energy

A principle stating that energy cannot be created or destroyed, only transformed from one form to another.

Work

The product of force and displacement in the direction of the force, defined mathematically as W = Fd cosθ.

Joule (J)

The unit of work and energy in the International System of Units (SI), equivalent to one newton-meter (N·m).

Scalar Quantity

A physical quantity that has magnitude but no direction, such as work.

Kinetic Energy (K)

The energy an object possesses due to its motion, calculated as K = (1/2)mv².

Potential Energy (U)

The energy stored in an object due to its position or configuration, such as gravitational potential energy, U = mgh.

Work-Energy Theorem

A principle stating that the work done on an object is equal to the change in its kinetic energy, W = ΔK.

Positive Work

Work done on an object that increases its energy, typically increasing its speed.

Negative Work

Work done on an object that decreases its energy, typically slowing it down.

Mechanical Energy

The sum of kinetic and potential energy in a system, expressed as E = K + U.

Conservative Force

A force that does not dissipate energy and for which the work done is path-independent, such as gravity.

Nonconservative Force

A force that dissipates energy, such as friction, where the work done is path-dependent.

Power

The rate at which work is done or energy is transferred, defined as P = W/t, measured in watts (W).

Watt (W)

The unit of power, equivalent to one joule per second (1 W = 1 J/s).

Work Done by a Variable Force

The work done when the force varies over the distance, calculated as the area under the force versus displacement graph.

Antiparallel Vectors

Vectors that are parallel but point in opposite directions, forming an angle of 180 degrees.

Coefficient of Kinetic Friction (μk)

A dimensionless constant that represents the frictional force between two moving surfaces.

Gravitational Potential Energy (Ug)

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