a) i) Define the term peak value and root mean square value of an alternating current. (02marks) ii) A resistor of 300Ω is connected to 240V a.c supply. Find the amplitude of the current through the resistor. (03marks) b) Fig.2 A coil of many turns of wire, a bulb and a battery are connected in series as shown in the diagram in fig.2 above. What is observed when switch s is closed and when it is opened?(02marks) Explain your observation in b (i) (04marks) c) A source of sinusoidal voltage of amplitude, and frequency, is V0, f, connected across a capacitor of capacitance c. derive an expression for the instantaneous current which flows. (03marks) d) Explain why the voltage at a generating power station must be stepped up to very high for long distance transmission. (02marks) e) i) What is rectification as applied to alternating current? (01mark) ii) With the aid of a diagram, describe how a half wave rectifier type of meter works. (03marks) SECTION D. a) What is meant by the term dielectric constant? (01mark) b) Describe an experiment you would carryout to verify that the capacitance
a) i) Define the term peak value and root mean square value of an alternating current. (02marks) ii) A resistor of 300Ω is connected to 240V a.c supply. Find the amplitude of the current through the resistor. (03marks) b) Fig.2 A coil of many turns of wire, a bulb and a battery are connected in series as shown in the diagram in fig.2 above. What is observed when switch s is closed and when it is opened?(02marks) Explain your observation in b (i) (04marks) c) A source of sinusoidal voltage of amplitude, V0, and frequency, f, is connected across a capacitor of capacitance c. derive an expression for the instantaneous current which flows. (03marks) d) Explain why the voltage at a generating power station must be stepped up to very high for long distance transmission. (02marks) e) i) What is rectification as applied to alternating current? (01mark) ii) With the aid of a diagram, describe how a half wave rectifier type of meter works. (03marks) SECTION D. a) What is meant by the term dielectric constant? (01mark) b) Describe an experiment you would carryout to verify that the capacitance
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