Answer:

direction is Horizontal
Explanation:
As we know that the string is horizontal here
so the tension force in the string is due to electrostatic force on it
now we will have

so here the force is tension force on it


now we have


direction is Horizontal
Given Information:
Number of turns = N = 1130 turns
Length of solenoid = L = 0.430 m
Magnetic field = B = 1.0x10⁻⁴ T
Required Information:
Current = I = ?
Answer:
I = 0.0302 A
Explanation:
The current flowing in the solenoid winding can be found using
I = BL/μ₀N
Where μ₀ is the permeability of free space, N is the number of turns, B is the magnetic field and L is the length of solenoid
I = 1.0x10⁻⁴*0.430/4πx10⁻⁷
*1130
I = 0.0302 A
or
I = 30.28 mA
Answer:
Explanation:
The volume of a sphere is:
V = 4/3 * π * a^3
The volume charge density would then be:
p = Q/V
p = 3*Q/(4 * π * a^3)
If the charge density depends on the radius:
p = f(r) = k * r
I integrate the charge density in spherical coordinates. The charge density integrated in the whole volume is equal to total charge.





Since p = k*r
Q = p*π^2*r^3 / 2
Then:
p(r) = 2*Q / (π^2*r^3)
Answer:
3.52176 x 10^-10 N
Explanation:
Fg = 3.52176 x 10^-10 Newton