Electrical Engineering MCQ|Objective questions Electrical Engineering|Industries Extension officer|Lecturer in Polytechnics set 3

Electrical Engineering MCQ|Objective questions Electrical Engineering|Industries Extension officer|Lecturer in Polytechnics set 3

Which of the following relation is incorrect 
(a) P = VI
 (b) P=I2R
(c) P= V∕R2
(d) P= V2∕R


 If I, R and t are the current, resistance and time respectively, then according to Joule‟s law heat produced will be proportional to 
(a) I2Rt 
(b) I2Rt2
(c) I2R2t 
(d) I2R2t2



 When a low resistance is connected in parallel with a high resistance, the combined
resistance is ( B )

(a) always more than the high resistance 
(b) always less than the low resistance
(c) always between the value of high and low resistance
(d) either lower or higher than low resistance depending on the value of high resistance

Two 100 W, 200 V lamps are connected in series across a 200 V supply. The total power consumed by each lamp will be watts. ( A )
(a)25 
(b) 50
(c) 100 
(d) 200


The factor which will have least effect on the voltage at the load end of a two-wire supply circuit is ( B )

(a) length of the circuit 
(b) whether supply frequency is 25 Hz or 50 Hz
(c) amount of load on the circuit 
(d) cross section of the current wires


For a given line voltage, four heating coils will produce maximum heat when connected
(a)all in parallel 
(b) all in series 
(c) with two parallel pairs in series 
(d) on pair in parallel with the other two in series


For current to flow, a circuit must be ( C )
(a) Isolated 
(b) insulated
(c) complete 
(d) protected


If a live‟ conductor of a public supply touches earth metal ( D )

(a) supply voltage will increase 
(b) supply voltage will decrease
(c) no current will flow 
(d) current will flow to earth


The material used for fuse must have 
(a) Low melting point and low specific resistance
(b) Low melting point and high specific resistance
(c) High melting point and low specific resistance

 Which of the following statements regarding a capacitor is not true? 
(a) dc cannot flow through it (b) ac can flow through‟ it
(c) current flows when a capacitor is connected for the first time across a battery

(d) slight moisture increases its capacitance