How would you calculate the speed at which the earth revolves around the sun in m/s?

1 Answer
Feb 21, 2016

Answer:

Calculate from the average distance of the Earth from the sun and the time it takes to complete one orbit as about #3xx10^4 ms^(-1)#

Explanation:

The average distance of the Earth from the Sun is spproximately #150# million km or #1.5 xx 10^11m#

The orbit of the Earth around the sun is roughly circular (more eliptical really, but let's keep it simple), with a period of roughly #365# days.

So the path that the Earth traverses in #365# days is approximately the circumference of a circle of radius #1.5 xx 10^11m#.

Use the formula #C = 2pir# to find that this is about #9.4 xx 10^11m#.

The number of seconds in #365# days is:

#365 * 24 * 60 * 60 = 31536000#

So the tangential velocity of the Earth is approximately:

#(9.4 xx 10^11) / (3.1536 xx 10^7) ~~ 3 xx 10^4 m s^(-1)#

That is #30# km per second.

If you want more accuracy, get more accurate figures for the distance of the Earth from the sun at perihelion/aphelion and use a more accurate figure for the orbital period.