1. On which of the following planets water cycle is available ?
(1) Jupiter (2) Earth
(3) Mars (4) Venus
2. The asteroids revolve round the
Sun in between :
(1) Earth and Mars
(2) Mars and Jupiter
(3) Jupiter and Saturn
(4) Saturn and Uranus
3. Which of the following is called
the twin of the earth ?
(1) Neptune (2) Venus
(3) Mars (4) Saturn
4. Which amidst the following planets has its orbit closest to Sun ?
(1) Venus (2) Mars
(3) Jupiter (4) Uranus
5. The light from the Sun reaches
the Earth in about—
(1) 8 seconds (2) 8 minutes
(3) 10 seconds (4) 10 minutes
6. The surface temperature of the
sun is estimated as
(1) 6000 °C (2) 12000 °C
(3) 18000 °C (4) 24000 °C
7. Which one of the following planets has no moon?
(1) Mars (2) Neptune
(3) Mercury (4) Pluto
8. Which one of the following is
called a red planet ?
(1) Venus (2) Mercury
(3) Mars (4) Jupiter
9. Brightest planet in our solar system is
(1) Venus (2) Mercury
(3) Mars (4) Jupiter
10. The Milky Way Galaxy was first
observed by
(1) Galileo
(2) Maarten Schmidt
(3) Marconi
(4) Newton
Answers: 1. (2) 2. (2) 3. (2) 4. (1)
5. (2) 6. (1) 7. (3) 8. (3)
9. (1) 10. (1)
Explainations:
1. (2) The water cycle, also known as the hydrological
cycle or H2O cycle, describes the continuous movement
of water on, above and below the surface of the Earth.
Although the balance of water on Earth remains fairly
constant over time, individual water molecules can
come and go, in and out of the atmosphere. The water
moves from one reservoir to another, such as from
river to ocean, or from the ocean to the atmosphere,
by the physical processes of evaporation,
condensation, precipitation, infiltration, runoff, and
subsurface flow. In so doing, the water goes through
different phases: liquid, solid (ice), and gas (vapor).
2. (2) Asteroids, sometimes called minor planets, are small,
rocky fragments left over from the formation of our
solar system about 4.6 billion years ago. Most of this
ancient space rubble can be found orbiting the sun
between Mars and Jupiter. Asteroids range in size from
Ceres, about 952 km (592 miles) in diameter, to bodies
that are less than 1 km across. The total mass of all
the asteroids is less than that of Earth’s Moon.
3. (2) Venus is the second planet from the sun and a
close neighbor to the earth. It was named after the
Roman Goddess of Beauty. Venus is usually one the
brightest objects in the sky, which might be the reason
it got its name. It is quite similar to the planet earth
mainly in its size and a few other characteristics which
is why it is often considered the Earth’s twin. However,
surface conditions are not nearly the same making it
a quite inhospitable environment.
4. (1) Venus is the brightest planet in our sky and can
sometimes be seen with the naked eye if we know
where to look. It is the solar system’s brightest planet
— yellow clouds of sulfuric acid reflect the sun’s light
brightly and has its orbit closest to sun but only next
to mercury.
5. (2) Light travels at 186,000 miles a second at the Earth
is 93 million miles to Sun on average. This works out
as 8.33 minutes for light from the Sun to reach Earth.
On average, it takes energy between 10,000 and
170,000 years to leave the sun’s interior and then be
emitted from the surface as light. Sunlight, in the
broad sense, is the total frequency spectrum of
electromagnetic radiation given off by the Sun,
particularly infrared, visible, and ultraviolet light. On
Earth, sunlight is filtered through the Earth’s
atmosphere, and is obvious as daylight when the Sun
is above the horizon.
6. (1) The surface of the sun is called the photosphere.
The photosphere is 340 miles thick and it’s temperature
s range from 5,500°C to 6,000°C. It has dark spots
called sunspots which are the only solar activity
observable by the naked eye.
7. (3) Mercury and Venus are the only two recognized
planets in our solar system without moons. However,
there are many, many planets in the universe and a
significant portion of these, if our solar system is
assumed representative of at least a significant portion
of the universe’s planetary systems likely have no
moons.
8. (3) Mars is the fourth planet from the Sun and the
second smallest planet in the Solar System. Named
after the Roman god of war, it is often described as
the “Red Planet”, as the iron oxide prevalent on its
surface gives it a reddish appearance. Mars is a
terrestrial planet with a thin atmosphere, having
surface features reminiscent both of the impact craters
of the Moon and the volcanoes, valleys, deserts, and
polar ice caps of Earth.
9. (1) Venus has the highest albedo of any planet in our
solar system. Venus is so bright partly because it
reflects over 70 per cent of sunlight striking it. It owes
its reflective ability to the fact that it’s blanketed with
clouds. Sunlight bouncing from these clouds is what
makes Venus so bright.
10. (1) The Milky Way is the galaxy that contains our solar
system. This name derives from its appearance as a
dim “milky” glowing band arching across the night sky,
in which the naked eye cannot distinguish individual
stars. Observational evidence for the Milky Way being
made up of distant stars first came when Galileo
pointed his telescope towards the Milky Way, observing
a large amount of faint stars.