Correct Answer: if the three forces acting at a point are in equilibrium, then each force is proportional to the sine of the angle between the other two
4. A lead ball with a certain velocity is made to strike a wall, it falls down, but rubber ball of same mass and with same velocity strikes the same wall, it rebounds. Select the correct reason from the following:
Options
A. both the balls undergo an equal change in momentum
B. the change in momentum suffered by rubber ball is more than the lead ball
C. the change in momentum suffered by rubber ball is less than the lead ball
6. In a single threaded worm and worm wheel, the number of teeth on the worm is 50. The diameter of the effort wheel is 100 mm and that of load drum is 50 mm. The velocity ratio is
8. The frequency of oscillation of a compound pendulum is(where kG = Radius of gyration about the centroidal axis, and h = Distance between the point of suspension and C.G. of the body.)
A. is the turning effect produced by a force, on the body, on which it acts
B. is equal to the product of force acting on the body and the perpendicular distance of a point and the line of action of the force
C. is equal to twice the area of the traingle, whose base is the line representing the force and whose vertex is the point, about which the moment is taken