Physics question of earth and sun!!?

Question

Assuming that the earth revolves round the sun in a circular orbit of radius 1.5*10^8 km, calculate its angular speed, linear speed and centripetal acceleration

Please show all the calculations and the formulaes used, Thank u!

Answer 1

linear speed = dist/time

dist = circumference of orbit = 2 pi R where R=1.5x10^11 m

time = no. secs in a year = 3.15x10^7s

(do the calc for linear speed)

angular speed = angular displacement/time

angular displacement = 2 pi radians in one year, so divide 2 pi by the time (see above)

centripetal accel = v^2/r; use v from linear speed and r as the radius of the orbit

good luck

Answer 2

Hope this gets you started:

1 trip around the sun is 360 degrees, or 2pi radians, and takes 1 year.

Therefore the angular speed of the earth is 2pi/year.

Angular speed (in unites of radians/time) is related to linear speed by the following equation:

linear speed = angular speed x radius

Thus, the linear speed of the earth is something in the neighborhood of

9.4x10^8 km/year.

Sorry, but I don't remember how to get centripetal accel off the top of my head, but your book no doubt has a formula for you.