Electricity Tes...

An electric heater, operating at $$220\ V$$, boils $$5\ l$$ of water in $$5\ \text{minutes}$$. If it is used on a $$110\ V$$ line, it will boil the same amount of water in:

An electric bulb is rated '100 W, 250 V' . What is the resistance of bulb ?

A given wire of resistance $$1\,\Omega$$ is stretched to double its length. What will be its new resistance?

Choose the correct option.

A wire of 3 ohm resistance and 10 cm length is stretched to 30 cm length. Assuming that it has a uniform cross section, what will be its new resistance?

A wire of 9 ohm resistance having 30 cm length is tripled on itself. What is its new resistance?

A car bulb connected to a 12 volt battery draw 2 A current when glowing. What is the resistance of the filament of the bulb?

The rating of an electrical appliance is $$60 W$$, $$220 V$$. What is the safe limit of current in it, while in use ?

An electric bulb draws $$1.2$$ $$A$$ current at $$6.0\ V$$. The resistance of filament of bulb will be 

In our household applications, commercial unit of electricity is used. One unit is equal to: