Which of the following characteristics is not suitable for a fuse wire?
thin and short
thick and short
low melting point
higher resistance than rest of wiring
An electric fuse works on the :
chemical effect of current
magnetic effect of current
lighting effect of current
heating effect of current
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
Which unit could be used to measure current?
Ampere
Volt
Coulomb
Watt
A 100 W,220 V bulb is connected across 110 V supply.The actual power consumed by the bulb will be
25 W
50 W
100 W
200 W
The potential difference between the terminals of an electric iron is 240 V and the current is 5.0 A. What is the resistance of the electric iron?
48 Ω
4.8 Ω
0.48 Ω
480 Ω
What is the order of magnitude of electric resistance of the human body (dry)?
102 ohm
104 ohm
106 ohm
108 ohm
The elements of electrical heating devices are usually made of :
tungsten
bronze
nichrome
argon
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
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
