1. What is the suitable material for electric fuse ?

Nichrome

Constantan

Cu

Tin-lead alloy

Answer: Tin-lead alloy

Explanation:


2. A cell of internal resistance r is connected to an external resistance R. The current will be maximum in R, if ?

R = r

R > r

R = r/2

R < r

Answer: R = r

Explanation:


3. A charge is moving across a junction, then ?

momentum will not be conserved.

at some places momentum will be conserved and at some other places momentum will not be conserved.

momentum will be conserved.

none of these.

Answer: none of these.

Explanation:


4. For measurement of potential difference, a potentiometer is preferred over voltmeter because ?

potentiometer is cheaper than voltmeter.

potentiometer does not take current from the circuit.

the resistance of potentiometer is less than voltmeter.

potentiometer is more sensitive than voltmeter.

Answer: potentiometer does not take current from the circuit.

Explanation:

For measurement of potential difference, a potentiometer is preferred over voltmeter because potentiometer does not take current from the circuit.


5. When a metal conductor connected to left gap of a meter bridge is heated, the balancing point ?

remains at zero

remains unchanged

shifts towards right

shifts towards left

Answer: shifts towards right

Explanation:


6. A metal wire is subjected to a constant potential difference. When the temperature of the metal wire increases, the drift velocity of the electron in it ?

decreases, thermal velocity of the electron decreases

increases, thermal velocity of the electron decreases

decreases, thermal velocity of the electron increases

increases, thermal velocity of the electron increases

Answer: decreases, thermal velocity of the electron increases

Explanation:


7. At temperature 0K, the germanium behaves as a / an ?

insulator

super-conductor

conductor

ferromagnetic

Answer: insulator

Explanation:


8. Appliances based on heating effect of current work on ?

only d.c.

only a.c.

both a.c. and d.c.

None of these

Answer: both a.c. and d.c.

Explanation:


9. In a wheatstone bridge in the battery and galvanometer are interchanged then the deflection in galvanometer will ?

not change

change in previous direction

change in opposite direction

none of these.

Answer: not change

Explanation:


10. The resistivity of alloy manganin is ?

Decreases with increase in temperature

Increases rapidly with decrease in temperature

Nearly independent of temperature

Increases rapidly with increase in temperature

Answer: Nearly independent of temperature

Explanation: