Engineering Mechanics In a screw jack, the effort required to lift the load is given by (where W = Load lifted, α = Helix angle, and φ = Angle of friction.) P = W cos (α + φ) P = W tan (α + φ) P = W tan (φ - α) P = W tan (α - φ) P = W cos (α + φ) P = W tan (α + φ) P = W tan (φ - α) P = W tan (α - φ) ANSWER DOWNLOAD EXAMIANS APP
Engineering Mechanics 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, P + m.a = 0 P × m.a = 0 P/m.a = 0 P - m.a = 0 P + m.a = 0 P × m.a = 0 P/m.a = 0 P - m.a = 0 ANSWER DOWNLOAD EXAMIANS APP
Engineering Mechanics The centre of gravity of a uniform lamina lies at The midpoint of its axis All of these The centre of heavy portion The bottom surface The midpoint of its axis All of these The centre of heavy portion The bottom surface ANSWER DOWNLOAD EXAMIANS APP
Engineering Mechanics For a self locking machine, the efficiency must be 1 Equal to 50% Less than 50% Greater than 50% 1 Equal to 50% Less than 50% Greater than 50% ANSWER DOWNLOAD EXAMIANS APP
Engineering Mechanics If the resultant of two equal forces has the same magnitude as either of the forces, then the angle between the two forces is 30° 90° 60° 120° 30° 90° 60° 120° ANSWER DOWNLOAD EXAMIANS APP
Engineering Mechanics Moment of inertia of a triangular section of base (b) and height (h) about an axis passing through its vertex and parallel to the base, is __________ than that passing through its C.G. and parallel to the base. Nine times Six times Four times Two times Nine times Six times Four times Two times ANSWER DOWNLOAD EXAMIANS APP