Engineering Mechanics - Study Mode
[#86] If ‘P’ is the force acting on the body, ‘m’ is the mass of the body and ‘a’ is the acceleration of the body, then according to Newton's second law of motion,
Correct Answer
(B) P - ma = 0
[#87] The angle of inclination of the plane at which the body begins to move down the plane, is called
Correct Answer
(A) Angle of friction
Explanation
Solution: Angle of Friction: The angle of friction is the angle at which a body just begins to move down an inclined plane. It represents the maximum angle at which a body can rest on the inclined plane without sliding down. It is determined by the coefficient of friction between the surfaces in contact. Angle of Repose: The angle of repose is the maximum angle at which a pile of granular material remains stable without sliding or collapsing. It is the natural angle formed by loose particles such as sand, gravel, or powders when poured onto a flat surface. The angle of repose depends on factors such as the size, shape, and cohesion of the particles. While both angles relate to the stability of objects on surfaces, they describe different scenarios: the angle of friction pertains to solid bodies on inclined planes, while the angle of repose relates to granular materials forming natural slopes. Given the context of the question, which is about the angle at which a body begins to move down an inclined plane, the correct answer remains Option A: Angle of friction .
[#88] If n = number of members and y = number of joints, then for a perfect frame, n = ?
Correct Answer
(B) $$frac{2}{3}$$
[#89] The velocity ratio for the third system of pulleys is
Correct Answer
(D) 2n - 1
[#90] Dynamic friction as compared to static friction is
Correct Answer
(C) Less