Universal Units
There are six types of Energy. The first is Work. Work is the energy expended by exertion of a force(F) over a distance (d). Work is measured in the unit joules. Then there is Potential Energy which is a form of work done by moving a weight (w, (mass x gravity)) a vertical distance (H). Kinetic Energy is the energy when an object is in motion. Kinetic Energy Transitional is when a constant force is applied to an object with constant acceleration, meaning that the velocity is linear with time. this can be calculated with (1/2)mv^2. Kinetic Energy Rotational is when an object has energy if it is moving along a path or if it isn't. This can be calculated as (1/2)lw^2. (w) is the angular velocity or the rotational speed and (l) is the moment of inertia. Kinetic Energy Total is the addition of both transitional and rotational kinetic energy (KE = KET + KER). Finally there is Thermal Energy or Heat (Q) is energy that is associated with a change in temperature (T). It is a function of the mass of an object (m) and the Specific Heat (C). Q = mCT.
Power is energy per time. The SI unit of Power is a Watt (W), named after James Watt. He is also responsible for horsepower (hp) which is a unit of power originally used to quantify how the steam engine could replace the work completed by a horse. A Watt is defined as W = J/s.
An Electric Charge is just basically known as a charge (e). The charge of a proton is positive (e = +1) and a electron is negative (e = -1). The value of an elementary charge (e) is small so charge (Q) is quantified as a Coulomb [C]. A charge is also known as C = As. An Electric Current is the movement of charges in a solid material. Also shown as A = C/s. A charge moves from the negative terminal to the positive terminal. It is measured in Amperes (A) which is the movement of a coulomb (C) of charge past any point a second (s). Voltage is a measure of how much work is required to move an electric charge in the vicinity of other electric charges. It is measured in Volts (V) which is 1J/1C. Electrical Resistance (R) is a measurement of how difficult it is to move charges through material. It is measured in ohms (Ω). One ohm is one volt (V) per Ampere (A) so (Ω = V/A). Resistance is related to current and Voltage by Ohm's law (V = IR). Electric Power measures energy released and stored in electrical charges due to voltage and current. Shown as (P = VI), (P = VA),(P=(J/C)x(C/s) = J/s).
A Resistor is an object that has resistance to an electrical current. The power absorbed is converted to heat. The power absorbed is solved by (P = VI = (IR) I = I^2R) and (P = VI = V(V/R) = V^2/R).
A Capacitor is formed by arranging two conducting, low resistance plates very close together separated with a insulator with a very high resistance. Each plate having a wire connected to it. When a current is run through one of the two plates, electrons begin to build up on that plate because they cannot penetrate through the insulator. The build up of electrons repels the negative charges on the opposite plate which makes the opposite plate positive. Capacitance (C) is measured in Farads (F).
F = F/C. The energy stored in a capacitor is shown as E = (1/2)CV^2.
An Inductor is just a coil or a wire. If a current is run through the coil, a magnetic field is produced and each loop adds to the magnetic field creating a stronger field. If the source of a current pushing current through a wire is removed, the magnetic field will collapse. The collapsing of the magnetic field induces a current. Inductance (L) is measured in units of Henrys (H). The voltage across an inductor is known as V = L(dl/dt).
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