Stars and the Solar System - Exemplar Solutions 1
NCERT Exemplar Solutions
CHAPTER – 17
STARS AND SOLAR SYSTEM
MULTIPLE CHOICE QUESTIONS
1. Morning star is the name given to
(a) pole star
(b) star Sirius
(c) planet Jupiter
(d) planet Venus
(b) star Sirius
(c) planet Jupiter
(d) planet Venus
Ans: (d) planet Venus
Explanation: planet Venus appears in the eastern sky before the sunrise and sometimes appears in the western sky just after the sunset. Therefore it is often called a morning or an evening star.
2. Which of the following figures depicts the position of pole star correctly ?
(a)
(b) 
(c) 
(d) 
Ans: (a) 
Explanation: The polar star lies close to the axis of rotation of earth.
3. Sun appears to move from east to west around the earth. This means that earth rotates from
(a) east to west
(b) west to east
(c) north to south
(d) west to north
(b) west to east
(c) north to south
(d) west to north
Ans: (b) west to east
Explanation: The sun rise in the east and set in the west. This means that earth rotates from west to east.
4. An astronaut standing on the surface of the moon throws a ball upwards. The ball would
(a) directly fall down from the point it is released.
(b) hang in space.
(c) go up and then come back to the surface of the moon.
(d) keep going up never to come back.
(b) hang in space.
(c) go up and then come back to the surface of the moon.
(d) keep going up never to come back.
Ans: (c) go up and then come back to the surface of the moon.
5. Suppose a new planet is discovered between Uranus and Neptune. Its time period would be
(a) less than that of Neptune.
(b) more than that of Neptune.
(c) equal to that of Neptune or Uranus.
(d) less than that of Uranus.
(b) more than that of Neptune.
(c) equal to that of Neptune or Uranus.
(d) less than that of Uranus.
Ans: (a) less than that of Neptune.
Explanation: If a new planet is discovered between Uranus and Neptune. Its time period would be less than that of Neptune.
6. The change in seasons on the earth occurs because :
(a) the distance between the earth and the sun is not constant.
(b) the axis of rotation of the earth is parallel to the plane of its orbit.
(c) the axis of rotation of the earth is perpendicular to the plane of its orbit.
(d) the axis of rotation of the earth is tilted with respect to the plane of its orbit.
(b) the axis of rotation of the earth is parallel to the plane of its orbit.
(c) the axis of rotation of the earth is perpendicular to the plane of its orbit.
(d) the axis of rotation of the earth is tilted with respect to the plane of its orbit.
Ans: (d) the axis of rotation of the earth is tilted with respect to the plane of its orbit.
Explanation: The axis of rotation of the earth is not perpendicular to the plane of its orbit. The tilt is responsible for the changes of seasons on the Earth.
7. The first of a month is the new moon day. On fifteenth of the same month, which of the following figures would represent the phase of the moon ?
(a) 
(b) 
(c) 
(d) 
Ans: (a) 
Explanation: On fifteenth of the same month, the following figure will represent the moon.
