| 91. | Which of the following heating element is used in electric press? |
A. Copper wire | |
B. nichrome wire | |
C. lead wire | |
D. iron wire |
| 92. | ‘Degana’ located in Rajasthan is famous for the production of |
A. Limestone | |
B. marble | |
C. platinum | |
D. tungsten |
| 93. | Which of the following metals has such a low melting point that it melts in the hand itself? |
A. sodium | |
B. gallium | |
C. potassium | |
D. magnesium |
| 94. | Which of the following metals is used as a semiconductor in transistors? |
A. Copper | |
B. Germanium | |
C. graphite | |
D. silver |
| 95. | What is used as a neutron moderator in nuclear plants? |
A. heavy water | |
B. graphite | |
C. Cadmium and Boron | |
D. aluminium |
| 96. | Which of the following elements produces corrosion resistance in steel? |
A. tungsten | |
B. Chromium | |
C. nickel | |
D. magnesium |
| 97. | To increase the hardness of steel, the amount of which is increased |
A. Carbon | |
B. Manganese | |
C. Chromium | |
D. silicone |
| 98. | found free in nature |
A. Sleep | |
B. Silver | |
C. Copper | |
D. none of these |
| 99. | The rays of which of the following radioactive elements are used in the treatment of cancer? |
A. radium | |
B. strontium | |
C. barium | |
D. cobalt |
| 100. | The metal used along with iron in making wrought iron is |
A. aluminium | |
B. Chromium | |
C. tin | |
D. Carbon |