A. length of heating element should be decreased
B. length of heating element should be increased
C. length of heating element has no effect on heating if water
D. none of the above
Related Mcqs:
- When electric current passes through a bucket full of water, lot of bubbling is observeD. This suggests that the type of supply is____________?
A. A. C.
B. D. C.
C. any of above two
D. none of the above - Electric pressure is also called________?
A. resistance
B. power
C. voltage
D. energy - An instrument which detects electric current is known as_____________?
A. voltmeter
B. rheostat
C. wattmeter
D. galvanometer - The filament of an electric bulb is made of______________?
A. carbon
B. aluminium
C. tungsten
D. nickel - 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 - Electric current passing through the circuit produces_____________?
A. magnetic effect
B. luminous effect
C. thermal effect
D. chemical effect
E. all above effects - When electric current passes through a metallic conductor, its temperature rises. This is due to__________?
A. collisions between conduction electrons and atoms
B. the release of conduction electrons from parent atoms
C. mutual collisions between metal atoms
D. mutual collisions between conducting electrons - When current flows through heater coil it glows but supply wiring does not glow because______________?
A. current through supply line flows at slower speed
B. supply wiring is covered with insulation layer
C. resistance of heater coil is more than the supply wires
D. supply wires are made of superior material - A nichrome wire used as a heater coil has the resistance of 2 £2/m. For a heater of 1 kW at 200 V, the length of wire required will be_____________?
A. 80 m
B. 60 m
C. 40 m
D. 20 m - A rheostat differs from potentiometer in the respect that it_____________?
A. has lower wattage rating
B. has higher wattage rating
C. has large number of turns
D. offers large number of tapping
