A block of mass 10 kg is at rest on a horizontal surface. The coefficient of static friction between the block and the surface is 0.40. A light rope is attached to the block and pulled with a force T that makes an angle 30° above the horizontal.
(a) Calculate the minimum magnitude of T required to just start moving the block.
(b) Determine the magnitude of the frictional force acting on the block immediately before motion begins.
(Take g = 9.8 m s⁻².)