Correct Answer : Option (B) : 1.02
Explanation : á½°=180 – 2sin¯¹(D-d/2C). Factor=1+ (1.04-1)(180-174.8)/(180-170).
Correct Answer : Drums with helical grooves
Explanation : They have more bearing surface of the drum and prevent friction between adjacent turns of the rope.
Correct Answer : Increasingly centrifugal force in large sheaves
Explanation : Larger sheaves have higher centrifugal forces and higher cost because more material is used in their construction.
Correct Answer : Both bending and tensile stress
Explanation : There is direct tensile stress due to load being raised as well as bending stress.