The forces acting on the glider are the gravitational force, the lift force and the drag (air friction). The drag () and lift force () are a function of the angle that the wings have with the gliding direction. =122 with: =0.1+3∙10−32 =122 with: =0.2+0.1− 3∙10−32 In the above equations, is in decimal degrees. Calculate and plot the travelled ground distance as a function of the gliding angle . The gliding angle is the angle of the gliding direction with respect to the ground (see figure 1). Note that the angle is determined by the wing angle . What is the optimum wing angle and corresponding travelled maximum distance?