Answer:
-320 μJ.
Explanation:
Consider a point with an electrical charge of 
. Assume that 
is the electrical potential at the position of that charge. The electrical potential of that point charge will be equal to:
.
Keep in mind that since both and might not be positive, the size of the electrical potential energy might not be positive, either.
For this point charge,
; (that's -8.0 microjoules, which equals to 
)
.
Hence its electrical potential energy:
.
Why is this value negative? The electrical potential energy of a charge is equal to the work needed to bring that charge from infinitely far away all the way to its current position. Also, negative charges are attracted towards regions of high electrical potential. Bringing this 
negative charge to the origin will not require any external work. Instead, this process will release 320 μJ of energy. As a result, the electrical potential energy is a negative value.
Answer:
B = 0.546 T, F = 2.59 10⁻¹² N
Explanation:
The magnetic force is
F = q v x B
We can calculate the magnitude of the force and find the direction by the right hand rule
F = q v B sin θ
Let's use Newton's second law
F = m a
Acceleration is centripetal
a = v² / r
We substitute
q v B sin θ = m v² / r
The angle between the field and the radius of the circle is 90º so sin 90 = 1
q B = m v / r
B = m v / q r
Let's calculate ’
B = 1.67 10⁻²⁷ 2.97 10⁷ / (1.60 10⁻¹⁹ 0.568)
B = 0.546 T
The foce is
F = q v B
F = 1.60 10⁻¹⁹ 2.97 10⁷ 0.546
F = 2.59 10⁻¹² N
True.
A zero on the Kelvin temperature scale is also know as Absolute Zero because that is when the atom(s) have literally no kinetic energy.
