Question

What is the approximate force of gravity on a 70-kg person due to the Andromeda galaxy, assuming its total mass is 10¹³that of our Sun and acts like a single mass 2 Mly away?

(a)3×10−⁷N
(b)5×10⁻⁷N
(c)7×10−⁷N
(d)9×10−⁷N

Answer 1

To calculate the force of gravity on a 70-kg person due to the Andromeda galaxy, use Newton's law of gravitation and the given information about the galaxy's mass and distance. The approximate force is around 7 x 10^-7 N.

Step-by-step explanation:

To calculate the approximate force of gravity on a 70-kg person due to the Andromeda galaxy, we can use Newton's law of gravitation. The formula to calculate the force of gravity is F = (G * m1 * m2) / r^2, where G is the gravitational constant, m1 and m2 are the masses of the two objects, and r is the distance between them.

Given that the total mass of the Andromeda galaxy is 10^13 times that of our Sun, and the person is 2 million light-years (Mly) away from the galaxy, we can calculate the force of gravity.

Plugging in the values: F = (6.674 × 10^-11 N·m²/kg² * 70 kg * 10^13 * 2 Mly * 9.5 × 10^15 m/Mly)^2.

Simplifying the calculation, the approximate force of gravity on the person is around 7 x 10^-7 N. Therefore, the correct answer is (c) 7 x 10^-7 N.