Civil Engineering Mcqs

A semi-circular disc rests on a horizontal surface with its top flat surface horizontal and circular portion touching down. The coefficient of friction between semi-cricular disc and horizontal surface is i. This disc is to be pulled by a horizontal force applied at one edge and it always remains horizontal. When the disc is about to start moving, its top horizontal force will____________________?
  • (A)  remain horizontal
  • (B)  slant up towards direction of pull
  • (C)  slant down towards direction of pull
  • (D)  unpredictable
  • (E)  none of the above
Kinetic friction is the________________?
  • (A)  tangent of angle between normal reac-tion and the resultant of normal reac-tion and the limiting friction
  • (B)  ratio of limiting friction and normal reaction
  • (C)  the friction force acting when the body is just about to move
  • (D)  the friction force acting when the body is in motion
  • (E)  dynamic friction