The contact ratio of the contacting tooth is

Question

Statement for Linked Answer Q01 to Q03

A gear set has a pinion with 20 teeth and a gear with 40 teeth. The pinion runs at 30rev/s and transmits a power of 20KW. The teeth are on the 20⁰ full-depth system and have a module of 5mm. The length of the line of action is 19mm.                                              

1. The center distance for the above gear set in mm is

      (a) 140                                                                (b) 150

      (c) 160                                                                (d) 170

        2. The contact ratio of the contacting tooth is

      (a) 1.21                                                               (b) 1.25

      (c) 1.29                                                               (d) 1.33

        3. The resultant force on the contacting gear tooth is N is

      (a) 77.23                                                             (b) 212.20

      (c) 2258.1                                                           (d) 289.43