If the efficiency of a machine is to be high, what should be low __________?

Related Mcqs:

1. The substances which have a large number of free electrons and offer a low resistance are called____?

   A. insulators
   B. inductors
   C. semi-conductors
   D. conductors

2. Capacitor does not allow the sudden change of ?

   A. current
   B. voltage
   C. power
   D. None of the above

3. The property of a conductor due to which it passes current is called___________?

   A. resistance
   B. reluctance
   C. conductance
   D. inductance

4. Which of the following material has nearly zero temperature co-efficient of resistance_________?

   A. Manganin
   B. Porcelain
   C. Carbon
   D. Copper

5. The filament of an electric bulb is made of______________?

   A. carbon
   B. aluminium
   C. tungsten
   D. nickel

6. Which of the following quantities remain the same in all parts of a series circuit ____________?

   A. Voltage
   B. Current
   C. Power
   D. Resistance

7. 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

8. Copper wire of certain length and resistance is drawn out to three times its length without change in volume, the new resistance of wire becomes__________?

   A. 1/9 times
   B. 3 times
   C. 9 times
   D. unchanged

9. The condition for the validity under Ohm’s law is that_______________?

   A. resistance must be uniform
   B. current should be proportional to the size of the resistance
   C. resistance must be wire wound type
   D. temperature at positive end should be more than the temperature at negative end

10. Voltage dependent resistors are usually made from________________?

    A. Charcoal
    B. Silicon Carbide
    C. Nichrome
    D. Graphite