mechanical engineering basic concepts ojective questions with answers part5

Q1. Angle of ascent of cam is defined as the angle
(A) during which the follower returns to its initial position
(B) of rotation of the cam for a definite displacement of the follower
(C) through which the cam rotates during the period in which the follower remains in highest position
(D) moved by the cam from the instant the follower begins to rise, till it reaches its highest position

Q2. Angle of dwell of cam is defined as the angle
(A) during which the follower returns to its initial position
(B) of rotation of the cam for definite dis¬placement of the follower
(C) through which the cam rotates during the period in which the follower remains in the highest position
(D) moved by the cam from the instant the follower begins to rise, till it reaches its highest position

Q3. Shear stress induced in a shaft subjected to tension will be
(A) maximum at periphery and zero at center
(B) maximum at center
(C) uniform throughout
(D) None of these

Q4. In a belt drive, the pulley diameter is doubled, the belt tension and pulley width remaining same. The changes required in key will be
(A) increase key length
(B) increase key depth
(C) increase key width
(D) increase key width

Q5. In PERT analysis, critical path is obtained by joining events having
(A) positive slack
(B) negative slack
(C) zero slack
(D) None of these

Q6. Pessimistic time is
(A) the maximum time which an activity might require
(B) the average time required for a job
(C) the most probable time considering all conditions
(D) the minimum time in which an activity can possibly be accomplished

Q7. The shock absorbing capacity of a bolt can be increased by
(A) tightening it properly
(B) increasing shank diameter
(C) grinding the shank
(D) making shank diameter equal to core diameter of thread

Q8. When a bolt is subjected to shock loading, the resilience of the bolt should be considered in order to prevent breakage at
(A) shank
(B) head
(C) in the middle
(D) at the thread

Q9. In the crankcase method of scavenging, the air pressure is produced by
(A) supercharger
(B) centrifugal pump
(C) movement of engine piston
(D) reciprocating pump

Q10. Maximum impulse will be developed in hydraulic ram when
(A) waste valve closes suddenly
(B) supply pipe is long
(C) supply pipe is short
(D) ram chamber is large

Q11. Hydraulic accumulator is used for
(A) accumulating oil
(B) supplying large quantities of oil for very short duration
(C) generally high pressures to operate hydraulic machines
(D) supplying energy when main supply fails

Q12. A hydraulic intensifier normally consists of
(A) two cylinders, two rams and a storage device
(B) a cylinder and a ram
(C) two co-axial rams and two cylinders
(D) a cylinder, a piston, storage tank and control valve

Q13. A hydraulic accumulator normally consists of
(A) two cylinders, two rams and a storage device
(B) a cylinder and a ram
(C) two co-axial rams and two cylinders
(D) a cylinder, a piston, storage tank and control valve

Q14. Pressure intensifier increases the pressure in proportion to
(A) ratio of diameters
(B) square of ratio of diameters
(C) inverse ratio of diameters
(D) square of inverse ratio of diameters

Q15. According to fan laws, at constant weight of air or gas, the speed, capacity and pressure vary
(A) directly as the air or gas density
(B) inversely as square root of density
(C) inversely as density
(D) as square of density

Q16. According to fan laws, at constant pressure, the speed capacity and power vary
(A) directly as the air or gas density
(B) inversely as square root of density
(C) inversely as density
(D) as square of density

Q17. According to fan laws, at constant speed and capacity, the pressure and power vary
(A) directly as the air or gas density
(B) inversely as square root of density
(C) inversely as density
(D) as square of density

Q18. Principle of similitude forms the basis of
(A) comparing two identical equipment
(B) designing models so that the result can be converted to prototypes
(C) comparing similarity between design and actual equipment
(D) hydraulic designs

Q19. Cavitation will begin when
(A) the pressure at any location reaches an absolute pressure equal to the saturated vapour pressure of the liquid
(B) pressure becomes more than critical pressure
(C) flow is increased
(D) pressure is increased

Q20. Cavitation is caused by
(A) high velocity
(B) high pressure
(C) weak material
(D) low pressure