31. Which of the following statement is correct?
A. The kinetic energy of a body during impact remains constant.
B. The kinetic energy of a body before impact is equal to the kinetic energy of a body after impact.
C. The kinetic energy of a body before impact is less than the kinetic energy of a body after impact.
D. The kinetic energy of a body before impact is more than the kinetic energy of a body after impact.
32. The maximum efficiency of a screw jack is
33. In a framed structure, as shown in the below figure, the force in the member AC is numerically equal to the force in member BC.
34. The force which acts along the radius of a circle and directed towards the center of the circle is known as centripetal force.
35. Moment of inertia of a triangular section of the base (b) and height (h) about an axis through its base, is
C. bh3/ 12
D. bh3/ 36
36. Concurrent forces are those forces whose lines of action
A. lie on the same line
B. meet at one point
C. meet on the same plane
D. none of these
37. The tension in the cable supporting a lift is more when the lift is moving __________ with an acceleration.
38. According to the law of moments, if a number of coplanar forces acting on a particle are in equilibrium, then
A. their algebraic sum is zero
B. their lines of action are at equal distances
C. the algebraic sum of their moments about any point in their plane is zero
D. the algebraic sum of their moments about any point is equal to the moment of their resultant force about the same point.
39. If u1 and u2 are the velocities of two moving bodies in the same direction before impact and v1 and v2 are their velocities after impact, then the coefficient of restitution is given by
40. Two bodies of masses m1 and m2 are hung from the ends of a rope, passing over a frictionless pulley as shown in the figure below. The acceleration of the string will be