The resistance of a wire of length 300 m and cross section area 1.0 mm2 made of material of resistivity 1.0 x 10-7 Ωm is :
2 Ω
4 Ω
20 Ω
30 Ω
The heat produced by passing an electric current through a fixed resistor is proportional to the square of :
magnitude of resistance of the resistor
temperature of the resistor
magnitude of current
time for which current is passed
Pick the odd one out
ammeter
voltmeter
rheostat
odometer
A wire whose resistance is 90 Ω is cut into 3 pieces of equal lengths which are then arranged in parallel.Calculate the resistance of the combination.
10 Ω
1/10 Ω
30Ω
1/30Ω
A current of 0.5 A is drawn by a filament of an electric bulb for 10 minutes. Calculate the amount of electric charge that flows through the circuit.
200 C
300 C
400 C
100 C
The work done in moving a unit charge across two points in an electric circuit is a measure of :
current
potential difference
resistance
power
The property of a conductor to resist the flow of charges through it is called
conductivity
commutation
electropositivity
Assertion (A) : The temperature of a metal wire rises when an electric current is passed through it.
Reason (R) : Collision of metal atoms with each other releases heat energy.
Both A and R are true and R is the correct explanation of A
Both A and R are true but R is not a correct explanation of A
A is true but R is false
A is false but R is true
1kWh =
3.6 x 103J
3.6 x 106J
3.6 x 109J
none of these
The reciprocal of a resistance of a conductor is
conductance
capacitance
impedance
