Image
MCQ
327. A heavy ladder resting on floor and against a vertical wall may not be in equilibrium, if-
the floor is smooth, the wall is rough
the floor is rough, the wall is smooth
the floor and wall both are smooth surfaces
the floor and wall both are rough surfaces
331. Least force required to draw a body up the inclined. plane is W sin (plane inclination + friction angle) applied in the direction-
along the plane
horizontally
vertically
at an angle equal to the angle of friction to the inclined plane
332. Angle of friction is the-
angle between normal reaction and the resultant of normal reaction and the limiting friction
ratio of limiting friction and normal reaction
the ratio of minimum friction force to the friction force acting when the body is just about to move
the ratio of minimum friction force to friction force acting when the body is in motion
333. The resultant of the following three couples 20 kg force, 0.5 m arm, + ve sense 30 kg force, 1 m arm - ve sense 40 kg force, 0.25 m arm, + ve sense having arm of 0.5 m will be-
20 kg. (-ve) sense
20 kg. (+ve) serse
10 kg. (+ve) sense
10 kg. (-ve) sense
335. According to Lami's theorem-
three forces acting at a point will be in equilibrium
three forces acting at a point can be represented by a triangle, each side being proportional to force
if three forces acting upon a particle are represented in magnitude and direction by the sides of a triangle, taken in order, they will be in equilibrium
if three forces acting at a point are in equilibrium, each force is proportional to the sine of the angle between the other two
339. Which one of the following statements is not correct-
the tangent of the angle of friction is equal to coefficient of friction
the angle of repose is equal to angle of friction
the tangent of the angle of repose is equal to coefficient of friction
the sine of the angle of repose is equal to coefficient to friction