84) The bell crank levers used in railway signalling arrangement are of third type levers.

85) When spring index increases, the value of Wahl's stress factor

86) A shaft is subjected to a maximum bending stress of 80 N/mm² and maximum shearing stress equal to 30 N/mm² at a particular section. If the yield point in tension of the material is 280 N/mm² and the maximum shear stress the

87) The longitudinal stress is __________ of the circumferential stress.

88) The expression 0.175 - 0.841/T is the Lewis form factor for