Question

what could be duration of year if distance between earth and sun gets double

Answer 1

The distance between earth and sun is approx 150 million km. The second part requires Keplers 3rd law.

Explanation:

Keplers 3rd law states that the period (year) squared of a planet is proportional to its average orbital distance from the sun  cubed.

Mathematically;

P2A3=k (i)

where P is the period, A is the distance and k is a constant.

So, let's define P as being the Earth's period, Aas it's average distance and p as being the period when the orbit distance is a.

So, using equation (i) we can say that:

P2A3=k=p2a3

Now, let's set a=2A (so a3=8A3) and so therefore:

P2A3=p28A3

Cancelling out A3 gives:

P2=p28
8P2=p2

so

p=√8P2

and

p=√8P

So, about 3 times as long to orbit.

Answer 2

Hii,
Friend here's the answer you are looking for :-
if the distance of earth will be the world from the sun than the duration of year will be 4 times.
HOPE THE ANSWER WILL HELP YOU.