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Using the circuit diagram above. Calculate the total charge in the circuit

In Homes, electrical appliances and lamps are connected in parallel because

In an A.C circuit, the ratio of r.m.s value to peak value of current is

You are provided with cells, a potentiometer, an ammeter, a voltmeter, a bulb, a key, a jockey, and other necessary materials. Measure and record the emf E of the battery. Set up a circuit as shown in the diagram above. Close the key K and use the jockey to make a firm contact at J on the potentiometer wire such that PJ = x = 10cm. Take the record of the voltmeter reading V and the corresponding ammeter reading I. Evaluate log V and log I. Repeat the procedure for other values of x =20, 30. 40, 50, and 60cm. Tabulate your readings. Plot a graph with the log I on the vertical axis and log V on the horizontal axis. Determine the slope, s, of the graph. Determine the intercept, c, on the vertical axis. State two precautions taken to ensure accurate results. (b)i. How is the brightness of the bulb affected as x increases? Give a reason for your answer. ii. List two electrical devices whose actions do not obey ohm's law

Three 4Ω resistors connected in parallel have a potential difference of 16 V applied across them. What is the total current in the circuit?

Eddy currents can be reduced by

A galvanometer of internal resistance 50\(\Omega\) and full scale deflection of 20 mA is converted into a voltmeter by connecting a resistor of resistance 1950\(\Omega\) in series to it. Calculate the maximum voltage that can be read by the voltmeter

Which of the following factors does not affect the electric resistance of wire?

A positively charged glass rod is placed near the cap of a positively charged electroscope. The divergence of the leaf is observed to

Use the diagram above to calculate the current, I.

When a lead-acid accumulator is fully charged, evolution of gases occurs at the electrodes. Name these gases and the respective electrodes at which thcy are given off.

(a) State two factors which affect the mass of elements deposited during electrolysis. (b) List two non-electrolysis.

You are provided with a voltmeter V, a chemical cell/ battery E; two standard resistors R, and R a potentiometer a key K a jockey, and other necessary materials. Set up a circuit as shown in the diagram above. Close the key K. Make contact with the potentiometer wire AB using the jockey at a point C such that AC = x = 20cm Read and record the voltmeter reading Evaluate x\(^{-1}\) and v\(^{-1}\) Repeat the procedure for other values of x= 30, 40, 50, 60 and 80cm. Tabulate your readings. Plot a graph with V\(^{-1}\) on the vertical axis and x\(^{-1}\) on the horizontal axis, starting both axes from the origin (0, 0). Determine the: (a) slope, s, of the graph; (b) intercept, c, on the vertical axis. State two precautions taken to ensure accurate results. (b)i. State the two devices in which ohm's law does not apply. ii. A current of 1 A is supplied to two resistors of resistance 2\(\Omega\) and 3\(\Omega\) connected in parallel. Calculate the current in each resistor.

It takes 4 minutes to boil a quantity of water using an electrical heating coil. How long will it take to boil the same quantity of water using the same coil if the current is doubled? [Neglect any external heat losses]

Which of the following is not a part of the electro-magnetic spectrum?