Answer the following :

Give reason for the following:

a. A person in England can recognize the pole star easily than a person in Bengaluru.

b. Mercury is difficult to observe.

c. A day on Venus is longer than its year.

d. Green house effect is prominent on Venus.

(a) Pole star is also known as North Star. England is located in the northern hemisphere of the earth whereas Bengaluru which is present in Karnataka is located in the Southern hemisphere. Due to this it is easy to locate pole star from the England as compared to Bengaluru.

(b) Mercury is the nearest planet to the sun. It is most difficult to observe mercury because due to the brightness of sun mercury can’t be seen clearly or a good view of mercury can’t be obtained. Due to extreme brightness of sun mercury is too difficult to observe.

(c) Yes, given statement is true that a day on Venus is longer than its year. The time taken by a planet to complete one rotation on its axis is termed as day and Venus takes 243 days to complete one rotation on its axis. Whereas the time taken by a planet to revolve around the sun is termed as a year and Venus take 225 days to complete one revolution to complete one revolution.

Since, time of rotation on its own axis is greater than the time of revolution around the sun in Venus, a day on Venus is longer than its year.

(d) Yes, green house effect is prominent on Venus. It is due to the atmosphere that exists on the Venus. The atmosphere on Venus comprises of Carbon dioxide. Carbon dioxide is a green house gas. It entraps all the heat coming to the surface of Venus and therefore it is the hottest planet.

Due to abundance of carbon dioxide which is a greenhouse gas, green house effect is prominent on Venus.