(d) suddenly decreases
Ans: (a)
101. Which one of the following pairs of rays is electromagnetic in nature?
   [NDA 2010]
   (a) Beta rays and gamma rays
   (b) Cathode rays and X-rays
   (c) Alpha rays and beta rays
   (d) X-rays and gamma rays
Ans: (d)
102. The magnetic lines of force due to a bar magnet [NDA 2010]
   (a) intersect inside the body of the magnet
   (b) intersect at neutral points only
   (c) intersect only at North and South poles
   (d) cannot intersect at all
Ans: (d)
103. The specific resistance of a conducting wire depends upon- [NDA 2010]
   (a) Length of the wire, area of cross-section of the wire and material of the
       wire
   (b) Length of the wire and area of cross-section of the wire but not on the
       material of the wire
   (c) Material of the wire only but neither on the length of the wire nor on the
       area of cross-section of the wire
   (d) Length of the wire only but neither on the area of cross-section of the
       wire nor on the material of the wire
Ans: (b)
104. When X-rays are produced - [NDA 2010]
   (a) heat is generated at the target
   (b) heat is absorbed at the target
   (c) the temperature of the target remains constant
   (d) brilliant light is seen at the target
Ans: (a)
105. Which one of the statements given below is not correct? [NDA 2010]
                                            163