Lower pairs are those which have___________________?

Lower pairs are those which have___________________?

A. point or line contact between the two elements when in motion
B. surface contact between the two elements when in motion
C. elements of pairs not -held together mechanically
D. two elements that permit relative motion
E. none of the above

Kinematic pairs are those which have__________________?

Kinematic pairs are those which have__________________?

A. point or line contact between the two elements when in motion
B. surface contact between the two ele-ments when in motion
C. elements of pairs not held together mechanically
D. two elements that permit relative mo-tion
E. none of the above

Which of the following is false statement in respect of differences between machine and structure___________________?

Which of the following is false statement in respect of differences between machine and structure___________________?

A. Machines transmit mechanical work, whereas structures transmit forces
B. In machines, relative motion exists be-tween its members, whereas same does hot exist in case of structures
C. Machines modify movement and work, whereas structures modify forces
D. Efficiency of machines as well as structures is below 100%
E. Machines are run by electric motors, but structures are not