The formula is=1/2(m x v^2)
so = 1/2*(0.05)*(310)^2
ans is =2402.5 joules
number 2 because the curve demstrates the crest GOOD LUCK i hope i got you the correct answer if not sorry
Complete Question
A 10 gauge copper wire carries a current of 20 A. Assuming one free electron per copper atom, calculate the drift velocity of the electrons. (The cross-sectional area of a 10-gauge wire is 5.261 mm2.)
mm/s
Answer:
The drift velocity is 
Explanation:
From the question we are told that
The current on the copper is 
The cross-sectional area is
The number of copper atom in the wire is mathematically evaluated

Where
is the density of copper with a value 
is the Avogadro's number with a value 
Z is the molar mass of copper with a value 
So
Given the 1 atom is equivalent to 1 free electron then the number of free electron is

The current through the wire is mathematically represented as

substituting values

=> 
Answer:
n=2.053
Explanation:
We will use Snell's Law defined as:

Where n values are indexes of refraction and
values are the angles in each medium. For vacuum, the index of refraction in n=1. With this we have enough information to state:

Solving for
yields:

Remember to use degrees for trigonometric functions instead of radians!
Explanation :
When an electron jumps from one energy level to another, the energy of atom gets changed.
If a photon gets absorbed, the electron will move to higher energy levels and then fall back to the lower energy levels. Then each time a photon will be absorbed whose energy is given by difference between the initial and final energy levels i.e
In Balmer series, the transition is from higher energy levels to n = 2.
So, the necessary condition for Balmer series is that the electron should be at first excited state or n = 2 level as shown in figure.