The M.I. of hollow circular section about a central axis perpendicular to section as compared to its M.I. about horizontal axis is_________________?
(A) same
(B) double
(C) half
(D) four times
(D) one fourth
The C.G. of a plane lamina will not be at its geometrical centre in the case of a______________?
(A) right angled triangle
(B) equilateral triangle
(C) square
(D) circle
(D) rectangle
Which of the following is the locus of a point that moves in such a manner that its distance from a fixed point is equal to its distance from a fixed line multiplied by a constant greater than one________________?
(A) ellipse
(B) hyperbola
(C) parabola
(D) circle
(D) none of the above
If three forces acting in different planes can be represented by a triangle, these will be in________________?
(A) non-equilibrium
(B) partial equilibrium
(C) full equilibrium
(D) unpredictable
(D) none of the above
The co-efficient of friction depends upon________________?
(A) nature of surfaces
(B) , area of contact
(C) shape of the surfaces
(D) ail of the above.
If three forces acting in one plane upon a rigid body, keep it in equilibrium, then they must either__________________?
(A) meet in a point
(B) be all parallel
(C) at least two of them must meet
(D) all the above are correct
(D) none of the above
The algebraic sum of moments of the forces forming couple about any point in their plane is________________?
(A) equal to the moment of the couple
(B) constant
(C) both of above are correct
(D) both of above are wrong
(D) none of the above
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
(D) 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
(D) dynamic friction
Dynamic friction as compared to static friction is________________?
(A) same
(B) more
(C) less
(D) may be less of more depending on nature of surfaces and velocity
(D) has no correlation