JUST IN



Friday, 10 February 2017

Physics Formulas and terms in Electricity

Physics Formulas and terms in Electricity
Physics Formulas
Electricity 
Here are some formulas related to electricity. 
Ohm's Law 
Ohm's law gives a relation between the voltage applied a current flowing
across a solid conductor:
V (Voltage) = I (Current) x R (Resistance)


Power

In case of a closed electrical circuit with applied voltage V and resistance R, through which current I is flowing,
Power (P) = V2/R = I2R. . . (because V = IR, Ohm's Law)


Kirchoff's Voltage Law

For every loop in an electrical circuit:
ΣiVi = 0
where Vi are all the voltages applied across the circuit.

Kirchoff's Current Law

At every node of an electrical circuit:
ΣiIi = 0
where Ii are all the currents flowing towards or away from the node in the circuit.


Resistance

The physics formulas for equivalent resistance in case of parallel and series combination are as follows:
Resistances R1, R2, R3 in series:
Req = R1 + R2 + R3
Resistances R1 and R2 in parallel:
Req = R1R2
R1 + R2
For n number of resistors, R1, R2...Rn, the formula will be:
1/Req = 1/R1 + 1/R2 + 1/R3...+ 1/Rn
Capacitors


A capacitor stores electrical energy, when placed in an electric field. A typical capacitor consists of two conductors separated by a dielectric or insulating material. Here are the most important formulas related to capacitors. Unit of capacitance is Farad (F) and its values are generally specified in mF (micro Farad = 10 -6 F).
Capacitance (C) = Q / V
Energy Stored in a Capacitor (Ecap) = 1/2 CV2 = 1/2 (Q2 / C) = 1/2 (QV)
Current Flowing Through a Capacitor I = C (dV / dt)
Equivalent capacitance for 'n' capacitors connected in parallel:
Ceq (Parallel) = C1 + C2 + C3...+ Cn = Σi=1 to n Ci
Equivalent capacitance for 'n' capacitors in series:
1 / Ceq (Series) = 1 / C1 + 1 / C2...+ 1 / Cn = Σi=1 to n (1 / Ci)
Here
C is the capacitance
Q is the charge stored on each conductor in the capacitor
V is the potential difference across the capacitor

Parallel Plate Capacitor Formula:

C = kε0 (A/d)
Where
k = dielectric constant (k = 1 in vacuum)
ε0 = Permittivity of Free Space (= 8.85 × 10-12 C2 / Nm2)
A = Plate Area (in square meters)
d = Plate Separation (in meters)
Cylinrical Capacitor Formula:
C = 2π kε0 [L / ln(b / a)]
Where
k = dielectric constant (k = 1 in vacuum)
ε0 = Permittivity of Free Space (= 8.85 × 10-12 C2 / Nm2)
L = Capacitor Length
a = Inner conductor radius
b = Outer conductor radius

Spherical Capacitor Formula:

C = 4π kε0 [(ab)/(b-a)]
Where
k = dielectric constant (k = 1 in vacuum)
ε0 = Permittivity of Free Space (= 8.85 × 10-12 C2 / Nm2)
a = Inner conductor radius
b = Outer conductor radius

Inductors

An inductor is an electrical component which resists the flow of electrons or electric current through it. This property of inductance, in these devices, is caused by the electromotive force,Inductors in a Series Network created by magnetic field induced in them. The unit of inductance is Henry. Here are some important formulas associated with inductors.
Energy Stored in Inductor (Estored) = 1/2 (LI2)
Where, L is inductance and I is the current flowing through the inductor.
Inductance of a cylindrical air core Coil (L) = (m0KN2A / l)
Momentum and Energy Transformations in Relativistic Mechanics

Consider the same two frames (S, S') as in case of Lorentz coordinate transformations above. S' is moving at a velocity 'v' along the x-axis. Here again γis the Lorentz factor. In S frame (Px, Py, Pz) and in S' frame (Px', Py', Pz') are momentum components. Now we consider formulas for momentum and energy transformations for a particle, between these two reference frames in relativistic regime.

Component wise Momentum Transformations and Energy Transformations

Px = γ(Px' + vE' / c2)
Py = Py'
Pz = Pz'
E = γ(E' + vPx)
and
Px' = γ(Px - vE' / c2)
Py' = Py
Pz' = Pz
E' = γ(E - vPx)
Physical Formulas for Quantities in Relativistic Dynamics
All the known quantities in classical mechanics get modified, when we switch over to relativistic mechanics which is based on the special theory of relativity. Here are formulas of quantities in relativistic dynamics.
Relativistic momentum p = γm0v
where,
m0 is the rest mass of the particle.
Rest mass energy E = m0c2
Total Energy (Relativistic) E = (p2c2 + m02c4))
Momentum and Energy Transformations in Relativistic Mechanics

Consider the same two frames (S, S') as in case of Lorentz coordinate transformations above. S' is moving at a velocity 'v' along the x-axis. Here again γis the Lorentz factor. In S frame (Px, Py, Pz) and in S' frame (Px', Py', Pz') are momentum components. Now we consider formulas for momentum and energy transformations for a particle, between these two reference frames in relativistic regime.

Component wise Momentum Transformations and Energy Transformations

Px = γ(Px' + vE' / c2)
Py = Py'
Pz = Pz'
E = γ(E' + vPx)
and
Px' = γ(Px - vE' / c2)
Py' = Py
Pz' = Pz
E' = γ(E - vPx)
Physical Formulas for Quantities in Relativistic Dynamics
All the known quantities in classical mechanics get modified, when we switch over to relativistic mechanics which is based on the special theory of relativity. Here are formulas of quantities in relativistic dynamics.
Relativistic momentum p = γm0v
where
m0 is the rest mass of the particle.
Rest mass energy E = m0c2
Total Energy (Relativistic) E = (p2c2 + m02c4))




No comments:

Post a Comment

We love to hear from you!

Sign into the comment box, comment using your gmail account without entering verification text.

If you want to be notified when I reply your comment? Tick the Notify Me box.

any more question call us on phone +2348130676158 or email us using the links ozywin295@gmail.com and blazegain18@gmail.com

THANKS.