1. A child swings a toy of mass 0.05 kg on a string of length 1.9 m in a horizontal circle at constant speed so that the string is nearly horizontal. The toy has a period of 0.6 s. The amount of centripetal force in the string is most nearly
(A) 2 N (B) 5 N (C) 10 N (D) 20 N

2. For the same toy in a circular path as the previous problem, the net centripetal force on the toy and its acceleration are
(A) both radially inward. (B) perpendicular to each other. (C) both zero. (D) both tangent to the circle.