Practice Test – 2 -Chapter 12:Electricity

Two bulbs take 50 watts each when connected in parallel to 100 V source. The total power consumed by them when they are connected in series with the same source is

An electric bulb is rated 

The commercial unit of electric energy is kilowatt−hour (kWh), commonly known as:

Three 2Ω resistors are connected to form a triangle. The resistance between any two corners is?

A uniform wire is cut into 

A wire has resistance 

If the resistance in the circuit is increased four times by keeping the potential difference the same, the current in the circuit is ___________.

A conductor of resistance 3Ω is stretched uniformly till its length is doubled. The wire is now bent in the form of an equilateral triangle. The effective resistance between the ends of any side of the triangle in Ω

Two wires A and B of same material and same mass have radius 2r and r and the length of the wire B is half the length of the wire  A. If resistance of wire A is 34Ω, then resistance of B will be:

If 5 resistors of 2.5Ω each are connected in parallel then what would be its resultant resistance?

A constant voltage is applied between the two ends of a uniform metallic wire. Some heat is developed in it. The heat developed is doubled if

Two copper wires are of same length one of the twice as thick as the other. Then the resistance of the two wires are in the ratio of :

When three resistors of resistances 3Ω,4Ω and 5Ω are connected in parallel, the currents through them are in the ratio

Inside a cell in a closed circuit the conventional electric current

Which unit is not used in either the definition of the coulomb or the definition of the volt?

A toaster operating at 240V has a resistance of 120Ω. The power is

An electric kettle has two heating coils. When one of the coils is connected to an AC source, the water in the kettle boils in 10 min. When the other coil is used the water boils in 

When resistors are connected in parallel, the current divides in the ...................

In series combination of resistances:

Inside a cell in a closed circuit the conventional electric current: