Electricity and Magnetism Answers

Find the electric field intensity at a point 2cm away from charge 20 micro columb

The inductance of a tuning circuit of an AM radio is 4 mH. Find the capacitance of the circuit required for reception at 1200 kHz.

two equal positive charges q1 = q2 = 2 microcoulomb are located at x = 0, y = 0.30 metre and x = 0, y = - 0.30 metre respectively. what are the magnitude and direction of the electric force q1 and q2 exert on a third charge Q4 microcoulomb at x = 0.40 metre, y = 0?

two points charge q1=+25nC and q2=-75nC are separated by a distance of 3.0cm. Find the Magnitude and direction of electric force that exerts on q2 and electric force that q2 exerts on q1

Force is equal to

Good day. I would like to know what is the relationship between the surface area of a conductor and the current through it. Is there a formula to relate these two? Thank you in advance.

 A magnetic dipole ~m = mˆk is placed in an otherwise uniform external magnetic

field B~

ex = −B0

ˆk .

(a) Write an expression for the radial, polar and azimuthal components of magnetic

field B~ (r, θ, φ) due to ~m only . (1 mark)

(b) Show that in the combined field there exists a certain spherical surface centered

on the dipole through which no field lines pass, Find its radius. (2 marks)

(c) Sketch the magnetic field lines in the region around the dipole in presence of

B~

ex.

Two electric charges q₁ and q₂ are initially separated by distance r_i . When the two charges are moved farther apart, the magnitude of the electric force reduces three times the initial. How many times the separation distance between them increases?

A small sphere of charge q₁ = +8.00 x 10^-5 C is at a distance r = 2.67 m from another small sphere of charge q₂ = -6.00 x 10^-5 C (a) What is the magnitude of the attractive electric force between these two charged spheres? (b) How many excess protons are there in the small sphere with charge q₁ ? (c) How many excess electrons are there in the small sphere with charge q₂ ?

. How much kinetic energy does the object receive when an object with 7 coulombs of charge is accelerated using an electrical potential difference of 12 volts?