Electricity and Magnetism Answers

A non-conducting sphere of radius 10 cm carries a charge of uniformly distributed throughout its volume. At 5 cm from the centre of the sphere, the electric field is 2000 N/C and its orientation points outwards. Find a) the volume charge density of the sphere; b) the modulus of the electric field at 20 cm from the centre.

A circular copper waveguide has a radius of 0.4 cm and is filled with a dielectric material having 𝜀𝑟 = 1.5 and tan δ = 0.0002.

2.1.1. Identify the first four propagating modes and their cut-off frequencies.

2.1.2. For the dominant mode, calculate the attenuation due to dielectric loss and attenuation due to conductor loss at 20 GHz.

A circular copper waveguide has a radius of 0.4 cm and is filled with a dielectric material having 𝜀𝑟 = 1.5 and tan δ = 0.0002.

2.1.1. Identify the first four propagating modes and their cut-off frequencies.

2.1.2. For the dominant mode, calculate the attenuation due to dielectric loss and attenuation due to conductor loss at 20 GHz.

A wire having the diameter of 1.2 mm and resistively of 100 * 10 ^ - 1 * Omega * m at 0°C is connected. across a cell of emf

1.5 V and gives a current of 10 mA. Calculate the length of the wire.

A copper microstrip transmission line is to be designed for a 100 Ω characteristic impedance. The substrate is 0.51 mm thick, 𝜀𝑟 = 2.2 and tan δ = 0.001.

At 5 GHz, find:

3.1.1. The guide wavelength on the line (in cm) and;

3.1.2. The total attenuation in dB/cm.

850v is applied to a 720pF capacitor how much energy is stored

1. Two charges are on the x-axis. Charge q1 = +35 nC is at x = 3.00 cm while charge q2 = -65nC is at x = 6.00 cm. Find the

magnitude and direction of

a) the electric force that q1 exerts on q2; and

b) the electric force the q2 exerts on q1.

2. A positive charge of 10-8 coulombs (C) experiences a force of 0.95 N when located at a certain point in an electric field.

Find the intensity (magnitude) of the electric field at that point.

2. A particle with a charge of 5nC has a distance of 0.5m away from a charge of 9.5nC. What is

its electric potential energy?

3. Find the electric potential at a distance of 8cm from a 7.58pC charge.

4. What is the electric potential given 0.58m away from a 18uC charge?

5. Calculate the amount of electric potential energy possessed by 2.52x10^-10C at a point

where the electric potential is 4.7 Volts.

6. The electric potential at a distance of 0.92m from a point charge is -8.41x10^5 V. what is the

quantity of the point charge?

Two identical charges, 3.0 m apart, exert forces of magnitude 5.0 N on each other. What is the value of either charge?

1-5. Two point charges, q1 = 8 µC and q2 = -5 µC, are separated by a distance r = 0.1 m. What is the magnitude of the electric force? Note: 1 µC = 10-6 C.

6-10. Three positive point charges of 3.0 µC, 6.0 µC, and 2.0 µC, respectively, are arranged in a triangular pattern, as shown in the figure below. Find the magnitude and direction of the electric force acting on the 6.0 µC charge.