141. Which of the following represents a correct match ?

i) moveable hair method—The intercept on levelling staff is kept

constant and stadia hair interval is variable,

ii) fixed hair method—The intercept on levelling staff is variable and stadia hair interval is fixed,

iii) tangential hair method—The stadia hairs are not used.

142. The multiplying constant of a theodolite is

f/i

where f is focal length of object lens, i is stadia hair interval and d is the distance

between the optical centre of the object lens and the axis of the theodolite

143. If the staff is held normal to the line of sight and the angle of elevation and depression are kept same, then the horizontal distance between instrument station and staff station computed by observations will be

greater at an angle of elevation than at an angle of depression

144. If the intercept on a vertical staff is ob served as 0.75 m from a tacheometer, the horizontal distance between tacheometer and staff station is 75 m

145. For a tacheometer the additive and multiplying constants are respectively

0 and 100

146. If the focal length of the object glass is 25 cm and the distance from object glass to the trunnion axis is 15 cm, the additive constant is 0.4

147. If the spacing of cross hairs in a stadia diaphragm of a tacheometer is 1.2 mm and the focal length of object glass is 24 cm, then the multiplying constant of

tacheometer is 100

148. Overturning of vehicles on a curve can be avoided by using transition curve

149. Different grades are joined together by a vertical curve

150. The angle substended by the long chord of a simple circular curve at its centre is equal to vertical curve

151. A curve tangential to four straight lines and consisting of arcs of different radii is known as three centred compound curve

152. If the degree of a curve is 1°, then radius of the curve is equal to 1720 m

153. The length of the tangent of a curve of radius R and angle of deflection A is given by R tan (Δ/2)

154. The length of the long chord of a simple circular curve of radius R and angle of deflection A is

2R sin (Δ/2)

155. Setting out a simple curve by two theodolite method does not require

linear measurements

156. The radial offset at a distance X from the point of commencement of curve of radius R is given by

157. If r is the radius of curvature at any point of a transition curve and l is the distance from the beginning of the transition curve to that point, then for ideal transition lαl/r

158. If the angle of intersection and radius of simple circular curve are 120° and 700 m respectively, then length of long chord is 700 m

159. In a reverse curve, the superelevation provided at the point of reverse curvature is zero

160. Total angle of deflection of a transition curve is spiral angle /3

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