Geodesy - Relation Between the Coordinates

Question 1

1. The relation between altitude and latitude of the observer can be given as
   a) Equal
   b) Minimum
   c) Maximum
   d) Not equal

Answer 1

Answer: a
Explanation: Relation between the co-ordinates must be established in such a way that they might form a relation. In case of altitude and latitude, they must be equal so that they can satisfy the required relation in case of solving problem.

Question 2

2. The sign for the deflection angle depends upon _______________
   a) Altitude
   b) Zenith
   c) Celestial body
   d) Horizon

Answer 2

Answer: c
Explanation: The placement of star defines the sign of the deflection angle. If the star is below the equator, then negative sign is allocated and if it is above then positive sign is allocated. By the allocation of sign to the deflection angle it might help in the determination of relation between latitude and declination.

Question 3

3. Determine the latitude of the observer if the altitude of the pole is given as 23˚41ꞌ.
   a) 32˚14ꞌ
   b) 32˚41ꞌ
   c) 23˚14ꞌ
   d) 23˚41ꞌ

Answer 3

Answer: d
Explanation: The relation between latitude and the altitude can be given as
θ = α. So, the value of latitude of the observer can be given as
θ = 23˚41ꞌ.

Question 4

4. Find the latitude of the observer if the declination is about 54˚32ꞌ having a meridian zenith of about 10m.
   a) 64˚2ꞌ
   b) 64˚32ꞌ
   c) 46˚32ꞌ
   d) 64˚23ꞌ

Answer 4

Answer: b
Explanation: The latitude in case of declination and zenith can be given as
θ = δ + z. On substitution, we get
θ = 54˚32ꞌ +10
θ = 64˚32ꞌ.

Question 5

5. Find the difference of longitude between A = 30˚E and B = 160˚E.
   a) 130˚
   b) 310˚
   c) 13˚
   d) 30˚

Answer 5

Answer: a
Explanation: The difference can be calculated by
B – A = 160˚- 30˚ = 130˚. In case of change in direction, the angle must be subtracted or multiplied with 180. This will help in change in its direction.

Question 6

6. If longitudes of A and B are given as 32˚12ꞌ W, 44˚2ꞌ W having latitude 29˚24ꞌ. Find the distance in km between the points A and B.
   a) 19.54km
   b) 91.1km
   c) 11.9km
   d) 19.1km

Answer 6

Answer: d
Explanation: The distance can be calculated by
Distance = difference of longitude * cos latitude. On substitution, we get
Distance = (44˚2ꞌ W – 32˚12ꞌ W)*cos29˚24ꞌ * 1.852
Distance = 19.1km.

Question 7

7. Which of the following indicates the formula for hour angle of equinox?
   a) Hour angle of star- R.A of the star
   b) Hour angle of star+ R.A of the star
   c) Hour angle of star / R.A of the star
   d) Hour angle of star* R.A of the star

Answer 7

Answer: b
Explanation: The relation between right ascension and hour angle can be determined by using the hour angle of equinox, which can be given as hour angle of equinox = hour angle of star+ R.A of the star.

Question 8

8. The distance between the points in a celestial body can be determined by using __________
   a) Napier’s rule
   b) Celestial rule
   c) Zenithal rule
   d) Obligate rule

Answer 8

Answer: a
Explanation: Napier’s rule is used in the determination of the distance between two points. It also involves in the measurement of altitude and hour angle if the declination and latitude are known.

Question 9

9. Determine the zenith distance if the declination of star is given as 74˚32ꞌ and the latitude of the observer as 54˚21ꞌ.
   a) 0˚12ꞌ
   b) 2˚11ꞌ
   c) 20˚11ꞌ
   d) 20˚15ꞌ

Answer 9

Answer: c
Explanation: Here, declination of a star is greater than the latitude the,
Zenith distance = ZP – AP
Zenith distance = (90-θ)- (90-δ)
Zenith distance = 90-54˚21ꞌ-90+74˚32ꞌ
Zenith distance = 20˚11ꞌ.