From db5af94a4ff878e04b277d2a63a91df2304cb9b9 Mon Sep 17 00:00:00 2001 From: emile Date: Mon, 8 Oct 2018 15:43:41 +0200 Subject: added function force_acting that is used to calculate the force acting in between two given stars. --- forces/forces.go | 31 +++++++++++++++++++++++++++++++ 1 file changed, 31 insertions(+) create mode 100644 forces/forces.go (limited to 'forces/forces.go') diff --git a/forces/forces.go b/forces/forces.go new file mode 100644 index 0000000..4539d06 --- /dev/null +++ b/forces/forces.go @@ -0,0 +1,31 @@ +package forces + +import ( + "../structs" + "math" +) + +// forces_acting calculates the force inbetween the two given stars s1 and s2 +// The function return the force +func ForceActing(s1 structs.Star, s2 structs.Star) structs.Force { + // Gravitational constant + var G = 6.674 * math.Pow(10, -11) + + // Distance between the stars + var r21 = math.Sqrt(math.Pow(s2.C.X-s1.C.X, 2) + math.Pow(s2.C.Y-s1.C.Y, 2)) + + // Unit vector pointing from s1 to s2 + rhat := structs.Force{s2.C.X - s1.C.X, s2.C.Y - s1.C.Y} + + // Calculate how strong the star is affected + var F_scalar = G * (s1.Mass * s2.Mass) / math.Pow(math.Abs(r21), 2) + + // Calculate the overall force by combining the scalar and the vector + var Fx = F_scalar * rhat.X + var Fy = F_scalar * rhat.Y + + // Pack the forces in a force structur + F := structs.Force{Fx, Fy} + + return F +} -- cgit 1.4.1