Mars has a mass of about 6.68 × 10^23kg,

Mars has a mass of about 6.68 × 10^23kg,
and its moon Phobos has a mass of about
9 × 10^15kg.
If the magnitude of the gravitational force
between the two bodies is 4.46 × 10^15N,
how far apart are Mars and Phobos? The
value of the universal gravitational constant
is 6.673 × 10^−11N · m^2/kg^2
.
Answer in units of m.

-Shay

Let,
distance, = d
Mars mass, M = 6.68 × 10^23kg,
Phobos, m = 9 × 10^15kg.
Force, F = 4.46 × 10^15 N
gravitational constant, G = 6.673 × 10^−11 N m^2/kg^2

Since, F = G*M*m / d^2
d^2 = G*M*m / F =
OR,
d^2 = 6.673 × 10^−11*6.68*10^23*9*10^15 / 4.46*10^15 =

= 89.951 x 10^12
OR,
d = 9.484 x 10^6 meters >===================< ANSWER

m = your homework.

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