Electricity

According to Ohm's Law, the potential difference across the ends of a resistor is directly proportional to the ……… through it, provided its ............ remains constant.

• current, temperature

• temperature, current

• physical condition, temperature

• physical condition, current

If the potential difference across the ends of a conductor is doubled, the current flowing through it, ……….

• remain same

• is zero

• gets half

• gets doubled

The SI unit of current is ………

• volt

• watt

• ampere

• joule

Coulomb is the SI unit of:

• charge

• current

• potential difference

• resistance

Electric potential is a:

• sometimes scalar and sometimes vector

• neither scalar nor vector

• scalar quantity

• vector quantity

Which of the following gases are filled in electric bulbs?

• Helium and Neon

• Argon and Nitrogen

• Neon and Argon

• Argon and Hydrogen

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

• greater than 3 Ω

• less than 1 Ω

• equal to 2 Ω

• between 1 Ω and 3 Ω

Electric power is inversely proportional to

• voltage

• current

• temperature

• resistance

Electrical resistivity of any given metallic wire depends upon

• nature of the material

• its thickness

• its shape

• its length

The heating element of an electric iron is made up of:

• copper

• nichrome

• iron

• aluminium