Distance to the moon from the earth is 3.84xx10^8m and the time period of the moon's revolution is 27.3 days. Obtain the mass of the earth.

Distance to the moon from the earth is 3.84xx10^8m and the time period

1.	Distance to the moon from the earth is 3.84xx10^8m and the time period of the moon's revolution is 27.3 days. Obtain the mass of the earth.
Answer» Solution :`T^2` = `((4pi^2)/(GM))r^3 , M = `(4pi^2)/(T^2G) r^3` = `(4xx(3.14)^2 XX (3.84xx10^8)^3)/((27.3 xx 24 xx 60 xx 60)^2 xx 6.67 xx 10^(-11) M = `6.48xx10^(23)kg`