Geography ยท Physics

Geodesy and Celestial Mechanics

1,049 Questions

Geodesy and celestial mechanics questions explore Earth measurements, great circles, and planetary motions. These concepts form a crucial part of physical geography and astronomy in competitive exams. Practice these questions to grasp longitudinal and latitudinal calculations.

Longitude and latitude calculationsGreat circle conceptEarths axial precessionLagrangian pointsAtmosphere boundary

Geodesy and Celestial Mechanics Questions

Multiple choice

What is the period of the nutation of the Earth's axis?

  1. 18.6 years

  2. 23.5 years

  3. 27.3 years

  4. 365.25 days
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

The period of the nutation of the Earth's axis is 18.6 years. This is the time it takes for the Earth's axis to complete one full cycle of nutation.

Multiple choice

What is the amplitude of the nutation of the Earth's axis?

  1. 9.2 arcseconds

  2. 18.4 arcseconds

  3. 27.6 arcseconds

  4. 36.8 arcseconds
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

The amplitude of the nutation of the Earth's axis is 9.2 arcseconds. This is the maximum angle by which the Earth's axis can deviate from its mean position.

Multiple choice

What is the effect of the nutation of the Earth's axis on the Earth's longitude of ascending node?

  1. It causes the Earth's longitude of ascending node to increase

  2. It causes the Earth's longitude of ascending node to decrease

  3. It causes the Earth's longitude of ascending node to change direction

  4. It has no effect on the Earth's longitude of ascending node
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

The nutation of the Earth's axis has no significant effect on the Earth's longitude of ascending node. This is because the nutation is a very small effect and it does not cause any significant changes in the Earth's mass or velocity.

Multiple choice

During polar day, what is the approximate duration of daylight in the polar regions?

  1. 24 hours

  2. 12 hours

  3. 6 hours

  4. 3 hours
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

During polar day, the Sun remains above the horizon for a continuous period of 24 hours, resulting in constant daylight in the polar regions.

Multiple choice

What is the approximate duration of polar night in the polar regions?

  1. 24 hours

  2. 12 hours

  3. 6 hours

  4. 3 hours
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

During polar night, the Sun remains below the horizon for a continuous period of 24 hours, resulting in constant darkness in the polar regions.

Multiple choice

Where are the Aurora Borealis and Aurora Australis most commonly seen?

  1. Near the equator

  2. Near the poles

  3. In the middle latitudes

  4. All over the world
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

The Aurora Borealis and Aurora Australis are most commonly seen near the poles because the Earth's magnetic field lines are strongest there.

Multiple choice

What is the spatial resolution of the Indian Remote Sensing (IRS) satellites?

  1. 10 meters

  2. 20 meters

  3. 30 meters

  4. 50 meters
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

The spatial resolution of the IRS satellites is 20 meters. This means that each pixel in an IRS image represents an area of 20 meters by 20 meters on the ground.

Multiple choice

What is the distance between the Aditya-L1 satellite and the Earth?

  1. 1.5 million kilometers

  2. 2 million kilometers

  3. 2.5 million kilometers

  4. 3 million kilometers
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

The distance between the Aditya-L1 satellite and the Earth is 1.5 million kilometers.

Multiple choice

What is the approximate size of convective granules on the surface of the Sun?

  1. 100 km

  2. 1000 km

  3. 10,000 km

  4. 100,000 km
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Convective granules on the surface of the Sun are typically about 1000 km in size.

Multiple choice

What is the approximate range of convective velocities in the Sun's convection zone?

  1. 1 km/s

  2. 10 km/s

  3. 100 km/s

  4. 1000 km/s
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

The approximate range of convective velocities in the Sun's convection zone is about 1 km/s.

Multiple choice

What is the term used for the angle between the vertical and the line of sight to a celestial body?

  1. Altitude

  2. Azimuth

  3. Declination

  4. Latitude
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Altitude is the term used for the angle between the vertical and the line of sight to a celestial body.

Multiple choice

Which trigonometric function is used to calculate the latitude of a place?

  1. Sine

  2. Cosine

  3. Tangent

  4. Cosecant
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

The sine function is used to calculate the latitude of a place, using the formula (\phi = \sin^{-1}(\sin \delta \sin \phi_0 + \cos \delta \cos \phi_0 \cos t)).

Multiple choice

What is the term used for the angle between the true north and the magnetic north?

  1. Altitude

  2. Azimuth

  3. Declination

  4. Latitude
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Declination is the term used for the angle between the true north and the magnetic north.

Multiple choice

What is the term used for the angle between the horizon and the celestial equator?

  1. Altitude

  2. Azimuth

  3. Declination

  4. Latitude
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Latitude is the term used for the angle between the horizon and the celestial equator.

Multiple choice

What is the term used for the angle between the vertical and the line of sight to the horizon?

  1. Altitude

  2. Azimuth

  3. Declination

  4. Latitude
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Altitude is the term used for the angle between the vertical and the line of sight to the horizon.