Three equal resistors connected in series across a source of emf together dissipate 10 W of power. What will be the power dissipated in watt if the same resistors are connected in parallel across the same source of emf?
W
10W
30W
90W
Two 220 V, 100 W bulbs are connected first in series and then in parallel. Each time the combination is connected to a 220 V AC supply line. The power drawn by the combination in each case respectively will be
200 W, 150 W
50 W, 200 W
50 W, 100 W
100 W, 50 W
Direct current is passed through a copper sulphate solution using platinum electrodes. The elements liberated at the electrodes are
Copper at anode and sulphur at cathode
Sulphur at anode and copper at cathode
Oxygen at anode and copper at cathode
Copper at anode and oxygen at cathode
A battery of emf 10 V internal resistance 0.5Ω is connected across a variable resistance R. The value of R for which the power delivered in it is maximum is given by
0.5 Ω
1.0 Ω
2.0 Ω
0.25 Ω
In electrolysis the mass deposited on an electrode is directly proportional to
Current
Square of current
Concentration of solution
Inverse of current
If the cold junction of a thermocouple is kept at 0oC and the hot junction is kept at T0C, then the relation between neutral temperature (Tn) and temperature of inversion (Ti) is
Tn = 2Ti
Tn = Ti – T
Tn = Ti + T
A 4µF capacitor is charged to 400 V and then its plates are joined through a resistance of 1 kΩ. The heat produced in the resistance is
0.16 J
1.28 J
0.64 J
0.32 J
The total power dissipated in watts in the circuit shown here is
16
40
54
4
In producing chlorine through electrolysis 100 W power at 125 V is being consumed. How much chlorine per minute is liberated ? (ECE of chlorine is 0.367 x 10-6 kg/C)
17.6 mg
21.3 mg
24.3 mg
13.6 mg
The temperature of inversion of a thermocouple is 620oC and the neutral temperature is 300oC. What is the temperature of cold junction?
20oC
3200C
- 200C
40oC
