Question

Page 3 of 6 10. Which of the following is correct? a) The rotation axes of planets are always perpendicular to their orbital plane (the ecliptic). b) No planet's orbital inclination is more than 20 degrees from the ecliptic. c) Planets orbits are circular. d) Planets always rotate and revolve in the same direction. 11. Which of the following is not a real difference between asteroids and comets? a) Asteroids are made mostly of rock and comets are made mostly of ice. b) Asteroids orbit the Sun while comets just float randomly around in the Oort cloud. c) Most asteroids are located much nearer to the Sun than most comets. d) It is thought that comets are far more numerous than asteroids. 12. Which planet listed below has the most extreme seasons? a) Jupiter b) Uranus c) Mars d) Venus e) Mercury 13. Which of the following observations indicates that conditions on Mars may have been suitable for life in the past? a) There are very large extinct volcanoes on Mars. c) Mars has two small moons. e) There is a very deep and long canyon that extends across Mars. b) Mars has polar caps made of "dry ice." dThere are dried-up riverbeds on Mars. 14. From high to low, rank the following objects in the average density a) Venus, Earth, Sun, Saturn c) Sun, Saturn, Earth, Venus e) Sun, Venus, Earth, Saturn b) Earth, Sun, Venus, Saturn d) Earth, Venus, Sun, Saturn f) Saturn, Earth, Venus, Sun 15. Suppose Venus rotated as fast as Earth. How would this change its relative levels of volcanism, tectonics, and erosion? a) All would remain the same - they are independent of rotation. b) All three would be higher. c) All three would be lower. d) Levels of volcanism and tectonics would stay the same, but erosion levels would be higher. e) Levels of volcanism and tectonics would be higher, and erosion levels would stay the same. 16. Which of the following is the origin of almost all the large moons around the jovian planets? a) They were formed by condensation and accretion in a disk of gas around the planet. bThey are captured asteroids. c) They are captured comets. d) They are captured planets. e) They were formed by giant impacts. 17. Heat escapes from a planet's surface into space by thermal radiation. Planets radiate almost entirely in the wavelength range of the a) visible. e) X-rays. (b)infrared. d) ultraviolet. c) radio.

Answer 1

Q-10) Planets particularly rotates and revolves in the same direction excluding the exception case of Venus and Uranus. Although that revolve around the sun in the same direction as the other planets but their spinning is in different direction, and it is also estimated that earlier they were also spinning in the same direction as other planets, but then huge asteroid hit them and their direction of spinning changed.

And the rest of the option like planet orbit are elliptical and not circular.

So the option D is correct.

11) The main difference between asteroid and comet is there compostion that is given correctly in option A. And it is also true that most of the asteroids are located nearer to the Sun than most of the comets.

The only difference that is not much suitable is about the number of comet and asteroid. Although number of comets is higher than the number of asteroid but astronomers have discovered millions of asteroid and only 4000 comets, although they estimate that there are hundreds of billions comets in oort clouds.

So option D is correct.

12)Uranus has the most extreme seasons. Uranus lies sideways with respect to the plane of orbit around the sun. And it takes nearly 84 earth years to make a complete orbit around the sun, and each season like winter, summer, spring, autumn has a time period of 21 years each.

So option B is correct.

13) Although there is lot of conflict between the thoughts, but scientists have found the evidence of riverbeds as the gullies may have formed from the flowing water on the Mars.

So the option D is correct.