Electrical Resistance

Q.

Mention two reasons on why tungsten is used for making filament of the electric bulb.

Q. Why is tungsten used for making filaments in an electric bulb?

Q.

The filament of the bulb is made up of which material?

Q. Which of the following metals is proven to be the poorest conductor of electricity?

1. Gold
2. Tungsten
3. Silver
4. Iron

Q.

Why is the tungsten used almost exclusively for filament of electric lamps?

Q.

A long wire will have__________ of same width.

1. More resistance than short wire

2. Less resistance than short wire

3. Same resistance as short wire

4. More tensile strength

Q.

Why is tungsten wire used for making filaments

Q.

The filament is usually made of steel, a material that emits light when electricity is passed through it.

1. False

2. True

Q.

Two fuse wires of same length are rated 5A and 20 A. Which of the fuse wire is thicker and why?

Q.

Why is tungsten used for making filament in an electric bulb

Q. Arrange the following materials based on their electrical conductivity.
$Copper,Steel,Silver,Plastic$

1. $Copper>Steel>Silver>Plastic$
2. $Copper<Steel<Silver<Plastic$
3. $Silver>Copper>Steel>Plastic$
4. $Silver<Copper<Steel>Plastic$

Q.

Two fuse wires of the same length are rated 5 A and 15 A. Which of the two fuse wires is thicker and why?

Q.

Which of the following can conduct electricity?

1. Air

2. Human body

3. Wood

4. Plastic

Q.

Why are alloy coils used in electric toasters and electric irons instead of pure metal?

Q.

Superconductors are materials that ___.

1. have no resistance

2. have considerable resistance

3. have very high resistance

4. have variable resistance

Q. which metal offers higher resistance to the passage of electricity other than copper