6thNational Astronomy Olympiad
January 26, 2019
F.M.: 90 Duration: 2 Hours
Symbol No.: ……………. Category: Junior
Note: Please read carefully before you proceed to answer the questions:
This question paper has objective and subjective section.
For objective Section: Please tick one of the best options available. If more than one options are marked, such
answers will not be considered for evaluation.
For subjective question: Please give your answer as creative as possible. Please do your best to include as
many steps as necessary.
OBJECTIVE SECTION
1. Which of the following is not a fundamental unit?
a. Second b. Coulomb
c. Ampere d. Candela
2. A car moves from Pokhara to Kathmandu with an average speed of 40 km/hr. It then moves back from
Pokhara to Kathmandu at an average speed of 60 km/hr. What is the average speed of the car for the
entirety of its trip?
a. 47 km/hr b. 48 km/hr
c. 49 km/hr d. 50 km/hr
3. The mean number of moons orbiting a planet in the solar system is 23.125 (this mean is defined as the
total number of moons orbiting planets divided by total number of planets). If over the next 10 years 30
additional moons are discovered, what is the new mean?
a. 26.875 moons per planet b. 26 moons per planet
c. 26.458 moons per planet d. 25 moons per planet
4. A person weighs 500 N on Earth. What is this person’s mass on Mars? (Assume Mars’ acceleration due
to gravity on its surface is half that of Earth’s, and use g=10 m/s2)
a. 250 N b. 25 kg
c. 500 kg d. 50 kg
5. The Moon rises almost 2 hours before the Sun has set on a particular day. Estimate the Moon’s phase.
a. Full Moon b. Waxing Gibbous
c. Waning Crescent d. First Quarter
6. What is the name of the rocket that carried the Apollo 11 module into space?
a. Saturn IV b. Saturn V
c. Titan V d. Titan IV
7. The current flowing through a wire is 3 A. Find the number of electrons that pass through the wire in 3
seconds. (the charge on one electron is approximately 1.6x10-19 C).
a. 5.625x1019 electrons b. 1.875x1019 electrons
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c. 6.25x10 electrons d. 6.25x1019 electrons
8. Kepler’s third law states that the square of the time period of revolution of a planet around the Sun is
directly proportional to the cube of the orbital radius of the planet. Using this law as fact, estimate a time
period for the revolution of a hypothetical planet in orbit around the Sun which orbits the Sun in a nearly
circular orbit at 100 times the Earth-Sun distance.
a. 100 years b. 1,000 years
c. 10,000 years d. 100,000 years
6thNational Astronomy Olympiad
January 26, 2019
9. The sine of an angle A is 6/10. Find the value of the sec A + tan A.
a. 2 b. 10/8
c. 6/8 d. 1
10. Which is the second brightest star in the night sky?
a. Sirius b. Alpha Centauri
c. Canopus d. Vega
11. How many light years are there in a parsec?
a. 2.3 light years b. 3.26 light years
c. 4.2 light years d. 2.6 light years
12. Which is the most massive object in our solar system?
a. Earth b. Jupiter
c. Saturn d. Sun
13. The famous cluster of stars, the Pleiades, lies in which constellation?
a. Taurus b. Orion
c. Ursa Major d. Centaurus
14. Which was the first spacecraft to visit the planet Uranus?
a. Voyager 1 b. Voyager 2
c. Pioneer 10 d. New Horizons
15. Which phenomena led to the discovery of Helium?
a. The absorption spectrum of the Sun b. Nuclear fusion of Hydrogen atoms
c. Nuclear fission d. X-ray diffusion
16. In astronomy, we are very interested in compounds that have an organic origin, because it has the
potential to indicate life on other worlds. What compounds are considered organic compounds?
a. Compounds made up of predominantly heavy metals like Iron
b. Compounds made up of predominantly radioactive substances like Uranium
c. Compounds made up of predominantly non-metals like Oxygen
d. Compounds made up of predominantly Carbon
17. It is well known that combustive phenomena, particularly in the presence of sulfur compounds, have
the ability to release Sulfur Dioxide gas as a by-product. During the course of scientific inquiry, it was
found that large amounts of Sulfur Dioxide was detected near the moon Io. Using your knowledge of
contemporary scientific fact, suggest the most suitable reason as to why the Sulfur Dioxide was found
there.
a. The presence of micro-organisms which release Sulfur Dioxide as a respiratory gas
b. The presence of an alien species which burns Sulfur compounds as a fuel source
c. The presence of volcanoes which release plumes of Sulfur Dioxide gas into the atmosphere
d. The gravitational interactions between Io and the Sun
18. Who is credited with the invention of the reflector telescope?
a. Galileo Galilei b. Robert Hooke
c. Nicholas Copernicus d. Sir Isaac Newton
19. The Sun is defined as the origin in a coordinate system. If the Earth has coordinates (3,6,10) in this
coordinate system, find the Earth-Sun distance in terms of these arbitrary units. Hint: Distance in 3D is
calculated in a similar way to that in 2D.
a. 11.89 b. 13.12
c. 12.04 d. 12.56
6thNational Astronomy Olympiad
January 26, 2019
20. What is the approximate time of sunrise for an observer located in Indonesia (close to the Equator) on
March 21st?
a. 7 am b. 6 am
c. 5 am d. 8 am
21. Which famous star is used as a reference to determine directions in the Northern Hemisphere?
a. Polaris b. Vega
c. Arcturus d. Sirius
22. How many planets in our solar system do not have moons?
a. 1 b. 2
c. 3 d. 4
23. How many planets in our solar system have rings?
a. 1 b. 2
c. 3 d. 4
24. Calculate the distance travelled by light in half a year. You are given the fact that the speed of light is
approximately 3x108 m/s.
a. 9.46x1015 m b. 9.46x1015 km
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c. 4.73x10 m d. 4.73x1015 km
25. If the Sun is located in the constellation of Capricorn, determine the season in the Northern
Hemisphere.
a. Autumn b. Winter
c. Summer d. Spring
26. Which country recently landed a probe on the far-side of the Moon?
a. India b. USA
c. Russia d. China
27. A bronze statue casts a shadow of 30 m when the Sun subtends an angle of elevation of 45 degrees.
What is the height of the statue?
a. 15 m b. 21.21 m
c. 30 m d. 42.42 m
28. What is the highest point in the sky called?
a. Nadir b. Zenith
c. Meridian d. Culmination
29. Which colours corresponding to the different wavelengths of light suffers from most atmospheric
scattering?
a. Blue b. Red
c. Orange d. Yellow
30. The focal length as measured using monochromatic red light of a convex lens is denoted A. The focal
length as measured using monochromatic blue light of a convex lens is denoted B. Then
a. B>A b. B=A
c. B<A d. B+A=constant for all lenses
***End of Objective Section***
6thNational Astronomy Olympiad
January 26, 2019
SUBJECTIVE SECTION
Note: Please use the answer-sheet provided to answer the following question. Please do not forget to write question no
including sub-section. Also don’t forget to write page number in each page.
1. An unbalanced force of 20 N acts on a body of 40 kg, initially at rest on a surface, for 30 seconds. We
assume that the surface is smooth. [10]
a. Calculate the velocity of the object after 30 seconds. (4)
b. Calculate the kinetic energy of the object after 30 seconds. (2)
We conduct the same experiment on a rough surface. We determine that the kinetic energy of the body
after 30 seconds in such a setting is 4000 J.
c. Determine the work done against friction. (2)
d. The surface is completely flat. Explain why we do not consider change in gravitational
potential energy in these situations.
(2)
2. Astronomers recently discovered a new star system in the constellation of Centaurus that has one star
and one planet. Using accurate measurements, the scientists determined that the mass of the star is
1.5x1029 kg and the mass of the planet is 1.3x1023 kg.
[10]
a. Determine an expression for the gravitational force between these two heavenly bodies in terms
of r. (3)
We know that the gravitational force provides (i.e. is equal to) the centripetal force that is needed for the
planet to maintain an orbit around its star. We also know that the expression for the centripetal force of
an object is mv2/r where m is the mass of the object, v is its velocity of revolution and r is the orbit
distance of the object from the central object. This can be summarized by this equation: mv2/r = GMm/r2
b. Using this expression for centripetal force, and assuming that the orbit is circular, determine
the orbital radius of the planet if its time period of revolution is 700 days.
(7)
3. The magnification of a particular telescope is given by the expression: focal length of objective/focal
length of magnifying lens. In this question, we shall be calculating the magnification of this telescope.
[10]
a. In an experiment with the objective lens, an image was formed 25 cm away when an object
was placed 25 cm from the lens. Find the focal length of the objective.
(4)
b. In an experiment with the magnifying lens, an image was formed 20 cm away when the object
was placed 5 cm from the lens. Find the focal length of the magnifying lens. (4)
c. Determine the magnification of the telescope. (2)
6thNational Astronomy Olympiad
January 26, 2019
***End of Subjective Section***
