Electric Circuits Answers

On threads of equal lengths of 50 cm and

negligible masses, about the same point

two balls of equal mass were hung

0.3 g each. When the balls are charged

equal amounts of the same

charges are reflected five times

less distance than length

the end. Calculate the charge of one

balls.

A 240 V two-bar electrical eadiator is rated 1 KW per bar. Calculate the resistance in the radiator circuit when one bar is switched on.

If a positive test charge is located between two charged spheres, A and B. Sphere A has a charge of +4q and is located 0.2 meter from the test charge. Sphere B has a charge of -2q and is located 0.1 meter from the test charge. If the magnitude of the force on the test charge due to sphere A is F, what is the magnitude of the force on the test charge due to sphere B?

Given a resistor R1= 20ohms, R2= 20ohms, R3= 30ohms are connected in parallel. The next one is connected in series to obtain a total resistance of 10ohms. If P= 0.36KW, Find the Current

Determine the equivalent total resistance for each of the following circuits below

7

5

2

The combination is connected to an external resistance of 24Ω.

Calculate;

a) the intensity of the current?

(2 mks)

b) the intensity of current if the cells are combined in parallel

(3 mks)

c) the intensity of current if the combination has two parallel series of two cells each.

Calculate the energy stored in a 5uf capacitor charge to 30 V

A 100 nC charge is placed at the origin. A -50 nC charge is placed at x= 5 cm and a 200 nC is placed at x= -10 cm.

b. What is the net electrostatic force acting on 200nC charge?

With the proper figures, describe the following terms in the context of Series R-L-C circuit

(i) Resonance Frequency (f0)

(ii) Power factor for f = f0,

(iii) Half-Power Bandwidth

(iv) Selectivity (Quality Factor) 

Name of the device 

Energy Transformation 

Wind-Up torch 

Match-Catching light 

Metal bubbling in solid 

Balloon being inflated 

Handle-turned generator and a bulb 

Battery and an electric bell