Adouble threaded worm drive has an axial pitch of 25 mm and a pitch circle diameter of 70 mm. the torque on the worm gear shaft is 1400 n-m. the pitch circle diameter of the worm gear is 250 mm and the tooth pressure angle is 25°. find : 1. tangential force on the worm gear, 2. torque on the worm shaft, 3. separating force on the worm, 4. velocity ratio, and 5. efficiency of the drive, if the coefficient of friction between the worm thread and gear teeth is 0.04.