Electricity and Magnetism Answers

A proton moving with a velocity of 3×10⁸ ms‐¹ perpendicularly in a magnetic field strength X T. Given that the force of the proton received is 4.8×10‐¹³ N. Find the value of X.

sound waves have a frequency of 250 Hertz and a wavelength of 1.30 meters. Find the speed of waves?

Consider a series circuit including a 4Ω, a 16mH-inductor, and a

power supply of 9 volts.

(a) Find the time constant of the RL series circuit?

(b) Find the current in the circuit 100μs after the switch is closed?

(c) How many times constant does it take for the current to reach 99.9% of its

final value?

A plate with an area A=0.09m"2 . An electric field E=80 N/C flows through the plate. The angle between the electric field and the surface of the plate is θ=50°.

Find the magnitude of the electric flow.

Water flows through a 2 cm radius hose at a speed of 4 m/s.

What must be the nozzle radius so that the water speed is at 16 m/s?

a) Calculate the intensity of a wave traveling in the air with an amplitude of 2 mm, a frequency of 400 Hz and at a speed of 150 m/sec.

Density of air at sea level is 1.225 Kg/m³.

A toroid core has N = 1200 turns, length L = 80cm, cross-sectional area A = 60cm2 , current I = 1.5A. Compute B and H. Assume an empty core. 

A proton moving with a velocity of 3 × 10^8 ms-1 perpendicularly in a magnetic field strength X T. Given that the force of the proton received is 4.8 × 10^-13 N. Find the value of X.

transformer connected to a 120-V (rms) ac line is to supply 12.0 V (rms) to a portable electronic device. The load resistance in the secondary is 5.00 Ω

Ω

.

(a) What should the ratio of primary to secondary turns of the transformer be?

(b) What rms current must the secondary supply?

(c) What average power is delivered to the load?

(d) What resistance connected directly across the 120-V line would draw the same power as the transformer? Show that this is equal to 5.00 Ω

Ω

 times the square of the ratio of primary to secondary turns.

An external voltage of 60 V is applied to a coil whose resistance is 5.25 Ω. What is the current in the coil if the back EMF is 9.85 Ω?