The Student Room Group
Reply 1
Because your title has to the power 11 and your working has to the power 8, maybe?

Either work in metres or km.
distance is wrong. you've used the radius not circumference.

basically you've calculated what the average speed of the earth would be if it took a year to crash directley into the sun
(edited 13 years ago)
Like, really really fast.
Reply 4
Original post by DumpOrStay?
Because your title has to the power 11 and your working has to the power 8, maybe?

Either work in metres or km.


I changed the distance to km because the answer in the book is given in km. If I do the same sum with x10^11 it's just 1000 x bigger :confused:
Reply 5
i = 1\sqrt -1
Reply 6
Original post by didgeridoo12uk
distance is wrong. you've used the radius not circumference.

basically you've calculated what the average speed of the earth would be if it took a year to crash directley into the sun


Ah ok.

So the distance given is the radius? So the correct sum would be


(2 x pi x 1.5x10^8) / (365*24*60*60)

= 29.8857...


Yay :smile:

Thanks
Reply 7
The motion is circular, so you must find the circumference of the orbit first.

Pi x diamter = 3.14 x (2x1.5x10^8)=9.24x10^8.

Then use speed = distance/time

Speed = 9.24x10^8) / (365x24x60x60)=29.885 kms^-1
becos its the radius u need to find the circumference of the earth 2*pi*r
the power of the question is not the same