A planet in another solar system orbits a star with a mass of kg

PHYSICS · Single correct · A Level · Physics · Fields and their consequences · Fields and their consequences

Problem

A planet in another solar system orbits a star with a mass of

4.0 \times 10^{30}

kg. Its perihelion distance is

175 \times 10^6

km and its semi-major axis is

250 \times 10^6

km. Take the universal gravitational constant to be

6.67 \times 10^{-11} \text{ m}^2/\text{s}^2 \text{ kg}

and calculate the speed of the planet at perihelion. The result is: (A) 21 km/s (B) 45 km/s (C) 51 km/s (D) 64 km/s