Pick up the wrong statement?
(A) In a heterogeneous or solid-fuel reactor, the fuel is mixed in a regular pattern within moderator.
(B) Slow or thermal neutrons have energy of the order or 0.025 eV
(C) Fast neutrons have energies above 1000 eV
(D) Fast reactor uses moderator
(D) Most serious drawback in using water as coolant in nuclear plants is its high vapour pressure
The angle which an inclined plane makes with the horizontal when a body placed on it is about to move down is known as angle of_______________?
(A) friction
(B) limiting friction
(C) repose
(D) kinematic friction
(D) static friction
In ideal machines__________________?
(A) mechanical advantage is greater than velocity ratio
(B) mechanical advantage is equal to velocity ratio
(C) mechanical advantage is less than velocity ratio
(D) mechanical advantage is unity
(D) none of the above
In actual machines_______________?
(A) mechanical advantage is greater than velocity ratio
(B) mechanical advantage is equal to velocity ratio
(C) mechanical advantage is less than velocity ratio
(D) mechanical advantage is unity
(D) none of the above
A cable with a uniformly distributed load per horizontal meter run will take the following shape________________?
(A) straight line
(B) parabola
(C) hyperbola
(D) elliptical
(D) part of a circle
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
Tangent of angle of friction is equal to__________________?
(A) kinetic friction
(B) limiting friction
(C) angle of repose
(D) coefficient of friction
(D) friction force
Limiting force of friction is the__________________?
(A) tangent of angle between normal-reaction and the resultant of normal reaction and 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) minimum force of 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