224) When a material is subjected to fatigue loading, the ratio of the endurance limit to the ultimate tensile strength is

225) The lead angle of a worm is 22.5 Degree. Its helix angle will be

226) The root angle of a bevel gear is equal to

227) The property of a bearing material which has the ability to accomodate small particles of dust, grit etc. without scoring the material of the journal, is called

228) The shock resistance of steel is increased by adding