1. Three resistors of 1 ohm, 2 ft and 3 ohm are connected in parallel. The combined resistance of the three resistors should be ?

between 1 ohm and 3 ohm

equal to 2 ohm

greater than 3 ohm

less than 1 ohm

Answer: less than 1 ohm

Explanation:


2. If the current I through a resistor is increased by 100 % (assume that temperature remains unchanged), the increase in power dissipated will be ?

200%

300 %

100%

400 %

Answer: 300 %

Explanation:


3. Electric potential is a ?

neither scalar nor vector

scalar quantity

vector quantity

sometimes scalar and sometimes vector

Answer: scalar quantity

Explanation:


4. Heat produced in a current carrying wire in 5s is 60J. The same current is passed through another wire of half the resistance. The heat produced in 5s will be ?

120 J

15 J

60 J

30 J

Answer: 30 J

Explanation:


5. Electrical resistivity of a given metallic wire depends upon ?

Its thickness

Nature of the material

Its shape

Its length

Answer: Nature of the material

Explanation:


6. Which of the following statement is or are correct ?

The simplest way to maintain a potential difference between the two ends of a conductor is to connect the conductor between the terminals of a cell or battery.

The electric current is a flow of electrons in a metal wire or conductor when a battery is applied across its ends.

Circuit is a continuous conducting path consisting of wires and switch between two terminals of a cell along which an electric current flow.

All the above

Answer: All the above

Explanation:


7. When electric current is passed, electrons move from ?

against the direction of the current

in the direction of the current

low potential to high potential

high potential to low potential

Answer: low potential to high potential

Explanation:


8. The resistance of hot filament of the bulb is about 10 times the cold resistance. What will be the resistance of 100 W-220 V lamp, when not in use ?

48.4 ohm

400 ohm

48 ohm

484 ohm

Answer: 484 ohm

Explanation:


9. Unit of electric power may also be expressed as ?

joule-second

watt-second

volt-ampere

kilowatt-hour

Answer: volt-ampere

Explanation:


10. Electrical resistivity of any given metallic wire depends upon ?

nature of the material

its length

its shape

its thickness

Answer: nature of the material

Explanation: