If the efficiency of a machine is to be high, what should be low?
A. Input power
B. Losses
C. True component of power
D. kWh consumed
E. Ratio of output to input
Author: Aroma Ann
Whether circuit may be AC. or D. C, which of the following is most effective in reducing the magnitude of the current?
A. Reactor
B. Capacitor
C. Inductor
D. Resistor
A glass rod when rubbed with silk cloth is charged because ___________?
A. it takes in proton
B. its atoms are removed
C. it gives away electrons
D. it gives away positive charge
Electric current passing through the circuit produces __________?
A. magnetic effect
B. luminous effect
C. thermal effect
D. chemical effect
E. all above effects
The thickness of insulation provided on the conductor depends on ___________?
A. the magnitude of voltage on the conductor
B. the magnitude of current flowing through it
C. both A. and (b)
D. none of the above
An electric filament bulb can be worked from __________?
A. D. C. supply only
B. A. C. supply only
C. Battery supply only
D. All above
The insulation on a current carrying conductor is provided __________?
A. to prevent leakage of current
B. to prevent shock
C. both of above factors
D. none of above factors
The hot resistance of the bulb’s filament is higher than its cold resistance because the temperature co-efficient of the filament is __________?
A. zero
B. negative
C. positive
D. about 2 ohms per degree
Which of the following quantities remain the same in all parts of a series circuit?
A. Voltage
B. Current
C. Power
D. Resistance
A closed switch has a resistance of __________?
A. zero
B. about 50 ohms
C. about 500 ohms
D. infinity
