Question

What is the gravitational force between a teacher of mass 90 kg and a student of mass 60 kg if the student sits on the front row 2 m from the teacher?

Answer 1

Question#19418

What is the gravitational force between a teacher of mass $90\,\mathrm{kg}$ and a student of mass $60\,\mathrm{kg}$ if the student sits on the front row 2 m from the teacher?

Solution:

According to Newton's law of universal gravitation the gravitational force is:

$$F = G \frac{M_1 M_2}{r^2}, \text{ were: } M_1, M_2 \text{ the masses of the bodies, r-distance}$$ $$G = 6.67384 \times 10^{-11} \,\mathrm{(m/kg)^2} \text{ gravitational constant}.$$ $$F = 6.67384 \times 10^{-11} \frac{90 \times 60}{2^2} = 9.01 \times 10^{-8} \,\mathrm{N}$$

Answer: $9.01 \times 10^{-8} \,\mathrm{N}$