Race Institute

#38, Burkit Road,

Opposite to bus terminal,

Thyagaraya Nagar

Chennai - 600 017.

Phone:

044-64563030

044-42660776

Mobile:

9043303030

Contact Person:

Bharath Seeman

 

1.The filament of an electric bulb is made of:

A. Iron

B. Nichrome

C. Tungsten

D. Graphite


Correct Answer is:c

Explanation:

Tungsten is a chemical element with the chemical symbol W and atomic number 74. The filament of an electric bulb is made of Tungsten which have an melting point of 3380 degree Celsius.

Iron is a chemical element with the symbol Fe and atomic number 26. It is a metal in the first transition series. It is the most common element (by mass) forming the planet Earth as a whole, forming much of Earth's outer and inner core.

Nichrome is a non-magnetic alloy of nickel, chromium, and often iron, usually used as a resistance wire. Patented in 1905, it is the oldest documented form of resistance heating alloy. A common alloy is 80% nickel and 20% chromium, by mass, but there are many others to accommodate various applications. It is silvery-grey in colour, is corrosion-resistant, and has a highmelting point of about 1400 C (2552 F).

Graphite is a type of mineral which is most known for its use in pencils. Graphite is carbon arranged in a very different way to how it is arranged in diamond. Pencils made out of the mineral graphite.