1. Venus has an equatorial radius of 6052 km. The semi-major axis of its orbit around the Sun is 0.72 AU. The smallest diameter of the primary mirror/lens (objective) of an optical telescope to be used to just resolve the Venus disc during the transit of Venus is approximately (a) 200 cm (b) 20 cm (c) 10 cm (d) 0.25 cm
2. The Earth’s atmosphere is transparent across the most of the optical region and ……….. region of the electromagnetic spectrum. Choose the correct option to fill the blank. (a) ultraviolet (b) X-ray (c) some portions of the radio wave (d) gamma-ray
3. It is given that the pupil of the human eye is about 5 mm (in diameter). How many times more light-gathering power does a telescope with a primary mirror of diameter about 20 cm (8 inches) have than the human eye? (a) 4 times (b) 16 times (c) 40 times (d) 1600 times
4. An astronomer observes a spectral emission line from a galaxy at a wavelength of 600 nm. This same spectral line is measured in the laboratory using a stationary source and is seen to have wavelength 500 nm. The speed of the galaxy toward or away from Earth (in units of the speed of light c) is equal to (a) 0.2 c moving away from Earth (b) 0.2 c moving toward Earth (c) 0.9 c moving away from Earth (d) 1.0 c moving toward Earth
5. An astronomer observes that Polaris is 40 degrees above her northern horizon. What can you say about the longitude of her location from her observations? (a) nothing (b) that it is 40 degrees north (c) that it is 50 degrees south (d) that it is 40 degrees east
6. The spectrum of a cloud of cool gas seen against a bright background black body would show (a) bright lines (emission spectrum) against a continuum spectral emission background (b) a continuous spectrum (c) dark lines (absorption lines) against a continuum emission background (d) either bright or dark lines, depending on distance, against a continuum emission background
7. If a star has a parallax of one-eighth of a second of arc, its distance from the earth is (a) 2,06,265 astronomical units (b) eight light years (c) one-eighth parsec (d) eight parsec
8. The elemental composition of the Sun, by mass, is about (a) 50 % metals, 50 % hydrogen (b) 71 % hydrogen, 27 % helium, 2 % others (c) 75 % helium, 20 % hydrogen, 5 % others (d) 75 % carbon, 25 % helium
9. Which of the following planets has essentially no atmosphere? (a) Venus (b) Mercury (c) Jupiter (d) Mars
10. Sunspots are (a) relatively cool compared to the photosphere (b) related to convection cells (c) related to the Sun’s electric field (d) cyclonic storms similar to Jupiter’s great red spot
11. A planet moves fastest in its orbit (a) when it is in opposition (b) when it is closest to the Sun (c) the greater its mass (d) when it is farthest from the Sun
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