How many days would there be in an year if the distance between the earth and the sun were reduced to half of its present value assuming circular orbit explain also?

Answer 1

Kepler's law says that reducing the size of the orbit by a factor of 2 reduces the duration of the revolution by the square root of 8, which means that a full revolution will be done in 129 days instead of 365.

====================================

Another contributor concurred:

Bravo. Before I saw this answer, I came up with 129.128 days,

assuming that both the initial and final orbits were circular.