The two elements of a pair are said to form a higher pair, when they

A. Have a surface contact when in motion

B. Have a line or point contact when in motion

C. Are kept in contact by the action of external forces, when in motion

D. Permit relative motion

Please do not use chat terms. Example: avoid using "grt" instead of "great".

You can do it
  1. The partial balancing of reciprocating parts in locomotives produces
  2. A body will begin to move down an inclined plane, if the angle of inclination of the plane is ________…
  3. The relation l = (2/3).(j + 2) apply only to kinematic chains in which lower pairs are used. This may…
  4. A simple spring-mass vibrating system has a natural frequency of fn. If the spring stiffness is halved…
  5. The component of the acceleration, perpendicular to the velocity of the particle, at the given instant…
  6. Inertia force acts
  7. In an open pair, the two elements of a pair
  8. When the sleeve of a Porter governor moves downwards, the governor speed
  9. For high speed engines, the cam follower should move with
  10. To obviate axial thrust, following gear drive is used
  11. The frictional torque transmitted in a truncated conical pivot bearing, considering uniform wear, is
  12. The natural frequency of free torsional vibrations of a shaft is equal to (where q = Torsional stiffness…
  13. The acceleration of a particle moving with simple harmonic motion, at any instant is given by
  14. A system of masses rotating in different parallel planes is in dynamic balance if the
  15. The velocity of the reciprocating roller follower when it has contact with the straight flanks of the…
  16. In a simple train of wheels, the velocity ratio __________ the intermediate wheels.
  17. The radial distance of a tooth from the pitch circle to the bottom of the tooth is called
  18. Idler pulley is used
  19. Typewriter constitutes
  20. The example of successfully constrained motion is a
  21. The centre of gravity of a coupler link in a four bar mechanism will experience
  22. A typewriter mechanism has 7 numbers of binary joints, six links and none of higher pairs. The mechanism…
  23. A reed type tachometer use the principle of
  24. Torsional vibrations are said to occur when the particles of a body moves
  25. The velocity of sliding of meshing gear teeth is (Where ω₁ and ω₂ are angular…
  26. A pulley and belt in a belt drive form a
  27. In order to give a complete secondary balance of a multi-cylinder inline engine,
  28. The centre distance between two meshing involute gears is equal to
  29. The load cup of a screw jack is made separate from the head of the spindle to
  30. The velocity of sliding __________ the distance of the point of contact from the pitch point.