0

can you help with this. Why in finding gravity the masses of two objects are multiplied. I don't understand the value of mass over gravity and why the masses are multiplied and then divided by distance. In one sentence I don't understand the idea of the gravity formula.

Thank you,

PowerPuffGirl
  • 71
  • 3
    It seems that you are not asking a math problem. Maybe http://physics.stackexchange.com is more suitable for your question. But I think this question has already been answered there. – Cave Johnson Nov 10 '16 at 14:07
  • Are you referring to $$G=\frac{m_1 m_2}{r^{2}}$$? –  Nov 10 '16 at 14:11
  • Yes, thank you, i'll check there – PowerPuffGirl Nov 10 '16 at 14:12
  • 1
    You may not understand it, because the teacher didn't show you a full proof. It takes some level of calculus to fully understand what's going on here, and they don't want to confuse the students. One thing you should note is the inverse-square law, which appears all the time in equations concerning radiation, forces acting at a distance, ect. – Kaynex Nov 10 '16 at 14:16
  • It's worth noting that the acceleration felt by an observer is given by: $$a = \frac{GM}{r^2}$$ Then, apply F = ma to get the equation above. – Kaynex Nov 10 '16 at 14:18
  • The best answer I've found on stackexchange so far is http://physics.stackexchange.com/a/81653, and that basically comes down to "we use that formula because that's the formula that matches the forces physicists observe." – David K Nov 10 '16 at 15:41
  • Crossposted to http://physics.stackexchange.com/q/291940/2451 – Qmechanic Nov 10 '16 at 23:09

0 Answers0