Image
MCQ
221. কাটিং টুলস (Cutting tools) তৈরি করা হয়-
নিকেল স্টিল দ্বারা
ক্রোম স্টিল দ্বারা
নিকেল ক্রোম স্টিল দ্বারা
হাই-স্পিড স্টিল দ্বারা
228. A sample of metal weighs 219 gms in air, 180 gms in water, 120 gms in an unknown fluid. Then which is correct statement about density of metal-
density of metal can't be determined
metal is twice as dense as water
metal will float in water
metal is twice as dense as unknown fluid
231. In the equation of virtual work, following force is neglected-
reaction of any smooth surface with which the body is in contact
reaction of a rough surface of a body which rolls on it without slipping
reaction at a point or an axis, fixed in space, around which a body is con-strained to turn
all of the above
233. D' Alembert's principle is used for-
reducing the problem of kinetics to equivalen statics problenz
determining stresses in the truss
stability of floating bodies
designing safe structures
236. Two spiral gears have a normal module of 10mm and the angle between the skew shaft axes is 50°. The driver has 20 teeth and the helix angle of it is 30°. If the velocity ratio is 1/3 and the driver as well as the follower are both left handed, find the centre distance between the shafts.
434.72mm
452.83mm
582.19mm
523.39mm