Question

Orbit of the earth around the sun is an ellipse with sun at one of its foci. If the semi-major axis is $150$ million kilometers and the eccentricity is $1/60$. The difference between the maximum and the minimum distance between the earth and the sun is equals to:

• A. $20$ million km
• B. $5$ million km
• C. $50$ million km
• D. $2.5$ million km

Answer 1

Answer: (B)

$5$ million km

Given $a=150$ and $e=\frac{1}{60}$

Difference btw maximum and minimum distance from the sun $=a(1+e)-a(1-e)$

$=2ae$

$=2\times 150\times \frac{1}{60}=5$ million km