Question

Since Venus rotates slowly, Fred Whipple thought that like Mercury, Venus keeps one face always towards the Sun. If so, he said that the dark side would be very cold. However, he knew with the help of earlier study carried out by Petit and Nicholson that it was not the case. So, he concluded that the planet must rotate fairly often to keep the darker side warmer.

Which of the following is the original premise?

Options

• Slow rotation of Venus

• Temperature of Venus

• Frequent rotation of Venus

• Equality of the rate of rotation and revolution

Answer 1

Slow rotation of Venus

Explanation:

The original premise was the ‘Slow Rotation of Venus’,  which was changed by the scientist on the basis of his later conclusions. Since this is the only fact given in the passage and the rest are all assumptions and observations, 'Slow rotation of Venus' is the apt answer.