Question

The acceleration due to gravity near the earth's surface is 9.8m/s2 and the earth's radius is 6400km. From this data calculate the mass of the Earth. Use any universal constant if required.

Answer 1

Since g = G*Me/ Re^2

=) 9.8m/s^2 = 6.67*10^-11 Nm^2 /kg^2 * Me / (6400*1000m)^2

=) 9.8m/s^2 = 6.67*10^-11 Nm^2 /kg^2 * Me /(6.4*10^6 m) ^2

=) 9.8m/s^2 = 6.67*10^-11 Nm^2 /kg^2 * Me / 40.96*10^12 m^2

=) 9.8 * 40.96 * 10^12 / 6.67*10^-11 = Me

=) 9.8*40.96/6.67 * 10^(12+11) = Me

=) 60.18 * 10^23 = Me

=) 6 * 10^24 kg

Hope it's helpful to u.

Answer 2

here answer about this question in photo