Correct Answer: The velocity ratio of a machine is the ratio of load lifted to the effort applied.
5. 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,
7. 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
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
9. The moment of the force P about O as shown in the below figure is