SI unit of specific resistance is
ohm m
(ohm)-1
(ohm m)2
ohm m-1
The device used for measuring potential difference is known as
voltmeter
galvanometer
voltameter
potentiometer
An electric fuse works on the :
chemical effect of current
magnetic effect of current
lighting effect of current
heating effect of current
The elements of electrical heating devices are usually made of :
tungsten
bronze
nichrome
argon
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
Which unit could be used to measure current?
Ampere
Volt
Coulomb
Watt
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
When an electric lamp is connected to 12 V battery,it draws a current of 0.5 A.The power of the lamp is
0.5 W
12 W
6 W
24W
The substance having infinitely high electrical resistance is called :
conductor
resistor
superconductor
insulator
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
