Maths
posted by Annie on .
Assuming that the planet Venus moves in a circular orbit of radiua 112 million km around the Sun and that it completes one revolution in 200 days, calculate the speed of Venus. Express your answer in scientific notation in km/h and use ð = 3 1/7.

Assume the orbit to be a circle. The orbital speed is
[2*(22/7)*112*10^6 km]/[(200 days)*24 h/day]
Do the numbers and round off to three significant figures 
uhm, is that
[2 x (22/7) x 112 x 10^6 km] / (200 days) x 24 h/day] ?
Where did the 22/7 come from? i calculated it and it came out to be 8.448 x 10^(7).
My textbook's answer says 1.47 x 10^(5) km/h.
could you further explain the question? and what you do with the pi.
Thanks :) 
I also calculated the expression given by drwls and got 1.4666 x 10^5
drwls used 22/7 because your question suggested to use pi = 3 1/7 or 22/7
(btw, I know why you got your incorrect answer, you must divide by both 200 and 24, you divided by 200 but then multiplied by 24) 
Assuming that the planet Venus moves in a circular orbit of radiua 112 million km around the Sun and that it completes one revolution in 200 days, calculate the speed of Venus. Express your answer in scientific notation in km/h and use ð = 3 1/7.
3 1/7 = 22/7
Orbit circumference = 2(112x10^6)22/7 = 7.04x10^8.
Orbital period = 200(24) = 4800 hours
Orbital velocity = 7.04x10^8/4800 = 1.46666x10^6 km/hr.
Rounded off = 1.47x10^5