Question

Two planets are orbiting a star in a distant galaxy. The first has a semimajor axis of 150 x 10^6 km, an eccentricity of 0.20, and a period of 1.0 Earth years. The second has a semimajor axis of 250 x 10^6 km, an eccentricity of 0.30, and a period of:

0.60 Earth yr

2.8 Earth yr

0.36 Earth yr

2.2 Earth yr

1.6 Earth yr

Answer 1

For a planet

T=time period

a=semi major axis of ellipse

Here for first planet

T=1 earth year

a=150xkm

..................(1)

For second planet T=?

a=250xkm

...................(2)

divide equation (2) by equation(1)

==4.632

T==2.2 earth year

Fourth option