Class 8
Chapter 17 Class 8 - Stars and the Solar System

The password to open the file is -  teachooisbest

## Morning star is the name given to

(a) pole star

(b) star Sirius

(c) planet Jupiter

(d) planet Venus

Sometimes Venus appears in the eastern sky before sunrise.

So, Planet Venus is known as the morning star

Therefore, (d) is correct

## 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.

Since moon has gravity, it will behave like the Earth.

So, the ball will go up and then come down.

Therefore, (c) is correct

## Do stars emit light only during night?

No, stars emit light all the time.

But, we are not able to see them because of the bright light of the sun

## John saw full moon on a particular day. After how many days will he be able to see the full moon again?

He will be able to see the full moon again after approximately 29 days.

After the full moon, the moon size decreases till no moon on the 15th day.

On 16th day, a small portion of moon appears. And it increases until we see a full moon

## Which planet is called morning star? Why is it called so?

The planet Venus is called the morning star.

Venus can be seen in the eastern sky just before the sun-rise, hence it is called the morning star.

## 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

(a) less than that of Neptune

Explanation

We know that,

The time period of a planet increases as its distance from the sun increases.

Since the new planet discovered lies between uranus and neptune,

Its distance from the sun would be more than uranus and less than neptune.

Hence, it’s time period will be more than that of uranus and less than that of neptune.

Learn in your speed, with individual attention - Teachoo Maths 1-on-1 Class