Answer: 
Explanation:
The kinetic energy of an electron 
is given by the following equation:
(1)
Where:
is the momentum of the electron
is the mass of the electron
From (1) we can find :
(2)
(3)
Now, in order to find the wavelength of the electron 
with this given kinetic energy (hence momentum), we will use the De Broglie wavelength equation:
(4)
Where:
is the Planck constant
So, we will use the value of found in (3) for equation (4):
(5)
We are told the wavelength of the photon 
is the same as the wavelength of the electron:
(6)
Therefore we will use this wavelength to find the energy of the photon 
using the following equation:
(7)
Where 
is the spped of light in vacuum
Finally:
Answer:
F = 2π I R B
Explanation:
The magnetic force is described by the equation.
F = q v x B = i L x B
Where i is the current, L is a vector that points in the direction of the current (length) and B is the magnetic field.
This equation can be used in scalar form and the direction of the force found by the right hand ruler, the thumb goes in the direction of L, the fingers extended in the direction of B and the palm of the hand indicates the direction of the force if the load is positive
F = i L B sin θ
In this case the wire is in the xy plane and the z-axis field whereby they are perpendicular, θ = 90º and sin 90 = 1
F = i L B
The loop length is
L = 2π R
F = i 2π R B
F = 2π I R B
The force is in the loop
Answer: The decibel scale is a logarithmic scale where each bel or 10 decibels correspondents to a factor of ten. A power intensity of 10^(-12) watts per square meter is the standard reference for a SPL of 0 db. So an SPL of 98 db corresponds to a power intensity of 10^(9.8)*10^(-12) or 10^(9.8–12) w/m^2.
0.006309573 w/m^2.
You can also readily find the value for any given SPL using the online calculator at: http://www.sengpielaudio.com/calculator-soundlevel.htm
Explanation:
The rays of the electromagnetic spectrum from shortest to longest wavelength are: radio waves, microwaves, infrared rays, optical rays, ultraviolet rays, X-rays, and gamma-rays.
EDIT: He has these backwards, the shortest wavelength is created by Gamma-Rays and the longest is Radiowaves.
<span> Remember- high energy = short wavelength. </span>
Because Na⁺ ion lacks an electron and O²⁻ has two extra electrons extra, to balance the charge, we need 2 Na⁺ ions.
All ions, atoms and molecules want to get to the minimum energy state, and that state is when the ion, atom, or molecule is neutral, that's why all of them want to balance their charges.
