The 10-lb block rests on a surface for which μk = 0.5. It is acted upon by a radial force...

The 10-lb block rests on a surface for which μk = 0.5. It is acted upon by a radial force of 2 lb and a horizontal force of 7 lb, always directed at 30° from the tangent to the path as shown. If the block is initially moving in a circular path with a speed v1 = 2 ft/s at the instant the forces are applied, determine the time required before the tension in cord AB becomes 20 lb. Neglect the size of the block for the calculation.