41. The difference in angle between magnetic north and true north is called:
42. What is the name for steel alloyed with chromium?
43. An antenna converts electric power into:
44. Which of the following is used in pencils?
45. What is the color of Nitrogen?
46. What is the melting point of iron?
47. Which is applied over steel or iron to prevent rusting?
48. The study of phenomena at very low temperatures is called:
49. What is the range of radio frequencies?
3 kHz to 300 GHz
20 kHz to 600 GHz
3 kHz to 300 kHz
200 kHz to 2000 kHz
50. What is the most commonly used semiconductor material?