Electromagnetic radiation can be described by its amplitude (brightness), wavelength, frequency, and period. By the equation
E = h ν E=hnu E=hν
, we have seen how the frequency of a light wave is proportional to its energy.
What is the basic equation of electromagnetism?
is the speed of light (i.e. phase velocity) in a medium with permeability μ, and permittivity ε, and ∇
2
is the Laplace operator. In a vacuum,
v
ph
= c
0
= 299792458 m/s
, a fundamental physical constant. The electromagnetic wave equation derives from Maxwell’s equations.
How do we calculate energy?
In classical mechanics, kinetic energy (KE) is
equal to half of an object’s mass (1/2*m) multiplied by the velocity squared
. For example, if a an object with a mass of 10 kg (m = 10 kg) is moving at a velocity of 5 meters per second (v = 5 m/s), the kinetic energy is equal to 125 Joules, or (1/2 * 10 kg) * 5 m/s
2
.
What is Maxwell’s third equation?
Maxwell’s 3rd equation is derived from Faraday’s laws of Electromagnetic Induction. It states that “
Whenever there are n-turns of conducting coil in a closed path which is placed in a time-varying magnetic field, an alternating electromotive force gets induced in each and every coil
.” This is given by Lenz’s law.
How do you calculate electrical energy?
Electrical energy is the product of power multiplied by the length of time it was consumed. So if we know how much power, in Watts is being consumed and the time, in seconds for which it is used, we can find the total energy used in watt-seconds. In other words,
Energy = power x time and Power = voltage x current.
How do you calculate energy in physics?
In terms of current and voltage it is
P=IV
. The energy used is the amount of charge q moved through voltage V in a time interval t. It is equal to the integral of power over time. A common unit used to describe energy usage is the kilowatt-hour, the energy of 1000 W acting over one hour.
How do you calculate energy in chemistry?
- add together the bond energies for all the bonds in the reactants – this is the ‘energy in’
- add together the bond energies for all the bonds in the products – this is the ‘energy out’
- energy change = energy in – energy out.
How do you calculate energy in joules?
In equation form:
work (joules) = force (newtons) x distance (meters)
, where a joule is the unit of work, as defined in the following paragraph. In practical terms, even a small force can do a lot of work if it is exerted over a long distance.
How do you calculate the number of photons from wavelength and energy?
According to the equation
E=n⋅h⋅ν
(energy = number of photons times Planck’s constant times the frequency), if you divide the energy by Planck’s constant, you should get photons per second.
What is Maxwell’s fourth equation?
The four Maxwell equations, corresponding to the four statements above, are: (1) div D = ρ, (2) div B = 0, (3) curl E = -dB/dt, and
(4) curl H = dD/dt + J
. In the early 1860s, Maxwell completed a study of electric and magnetic phenomena.
What is magnetic field formula?
A magnetic field can be produced by either a current, a flow of charged particles or a magnetised material. … The magnitude of the force on a wire carrying current I with length L in a magnetic field is given by the equation.
F=ILBsinθ
where θ is the angle between the wire and the magnetic field.
What is Q in Q MC ∆ T?
Q=
mc
ΔT Q = mc Δ T , where Q is the symbol for heat transfer, m is the mass of the substance, and ΔT is the change in temperature. The symbol c stands for specific heat and depends on the material and phase. The specific heat is the amount of heat necessary to change the temperature of 1.00 kg of mass by 1.00oC.
What is relation between E and V?
The relationship between V and E for parallel conducting plates is
E=Vd E = V d .
What does Q MC t mean?
Q = mc∆T. Q =
heat energy
(Joules, J) m = mass of a substance (kg) c = specific heat (units J/kg∙K) ∆ is a symbol meaning “the change in”
What is the energy in joules?
1 Joule (J) is the MKS unit of energy,
equal to the force of one Newton acting through one meter
. 1 Watt is the power from a current of 1 Ampere flowing through 1 Volt. 1 kilowatt is a thousand Watts. 1 kilowatt-hour is the energy of one kilowatt power flowing for one hour.
How do you calculate work energy and power?
work done
= force × distance moved in direction of force
. change in gravitational energy = mgh. power = work donetime taken, power = rate of energy transfer. power = force × velocity.
How do you calculate the power of a photon?
The rate of photons at a particular wavelength and power is calculated by use of the equation for photon energy,
E = hc/λ
(where h is Planck’s constant).
What is Maxwell’s first equation?
First Maxwell’s Equation:
Gauss’s Law for Electricity
The Gauss’s law of electricity states that, “the electric flux passing through a closed surface is equal to 1/ε0 times the net electric charge enclosed by that closed surface”.
How do you calculate the number of photons absorbed?
since you have the frequency of the light, you can calculate the energy of each photon with E = hf. with the energy of each photon and the total energy the surface has absorbed, you can calculate the number of photons by
dividing the total energy by the energy of an individual photon
.
What is Maxwell’s second law?
Therefore the net flux out of the enclosed volume is zero, Maxwell’s second equation:
∫→B⋅d→A=0
. The first two Maxwell’s equations, given above, are for integrals of the electric and magnetic fields over closed surfaces .
What is Maxwell equation in physics?
Maxwell’s equations are
a set of coupled partial differential equations that
, together with the Lorentz force law, form the foundation of classical electromagnetism, classical optics, and electric circuits. … Maxwell first used the equations to propose that light is an electromagnetic phenomenon.
What is EFQ Q?
Since electric field is defined as a force per charge, its units would be force units divided by charge units. In this case, the standard metric units are Newton/Coulomb or N/C. … The symbol q in the equation is
the quantity of charge on the test charge
(not the source charge).
What is V KQ R?
v=kq/r means
potential at r distance from and by q charge
. potential due to point charge at r distance. now about v=w/q it is another definition of voltage :- force acting at distance by unit charge. w = work = force×distance.
What is the relation between E and B?
| E = c | B |
|---|
What is magnetic moment formula?
Magnetic Moment Formula:
The magnetic moment is a vector relating torque of an object to the magnetic field. This is mathematically represented as:
τ = m × B
.
What is the formula of magnetic field B?
The Biot-Savart Law can be used to determine the magnetic field strength from a current segment. For the simple case of an infinite straight current-carrying wire it is reduced to the form
B=μ0I2πr B = μ 0 I 2 π r .
