<u>Answer:</u> The voltage needed is 35.7 V
<u>Explanation:</u>
Assuming that the resistors are arranged in parallel combination.
For the resistors arranged in parallel combination:
We are given:
Using above equation, we get:
Calculating the voltage by using Ohm's law:
.....(1)
where,
V = voltage applied
I = Current = 3.75 A
R = Resistance =
Putting values in equation 1, we get:
Hence, the voltage needed is 35.7 V
Answer:
E = 4.83 N/ C
Explanation:
If we have a uniform charge sphere we can use the following formulas to calculate the Electric field due to the charge of the sphere:
: Formula (1) To calculate the electric field in the region outside the sphere r ≥ a
Where:
K: coulomb constant (N*m²/C²)
a: sphere radius (m)
Q: Total sphere charge (C)
r : Distance from the center of the sphere to the region where the electric field is calculated (m)
Equivalences
1nC=10⁻⁹C
1cm= 10⁻²m
Data
k= 9*10⁹ N*m²/C²
Q=4nC=4 *10⁻⁹C
D = 26 cm = 26*10⁻²m = 0.26m
a = D/2 = 0.13m
r= R+a = 2.6 m+ 0.13m = 2.73m
Problem development
Magnitude of the electric field at r = 2.73m from the center of the sphere
r>a , We apply the Formula (1) :
E= 4.83 N/ C