# Engineering Mechanics – Section 2

11. The center of gravity of a semi-circle lies at a distance of __________ from its base measured along the vertical radius.

A. 3r/ 8
B. 4r/ 3π
C. 8r/3
D. 3r/4π

12. The process of finding out the resultant force is called __________ of forces.

A. composition
B. resolution

13. A weight of 1000 N can be lifted by an effort of 80 N. If the velocity ratio is 20, the machine is

A. reversible
B. non-reversible
C. ideal

14. In a framed structure, as shown in the below figure, the force in the member BC is  15. The potential energy of a vertically raised body is __________ the kinetic energy of a vertically falling body.

A. equal to
B. less than
C. greater than

16. If a number of forces acting at a point be represented in magnitude and direction by the three sides of a triangle, taken in order, then the forces are not in equilibrium.

A. Agree
B. Disagree

17. The periodic time of a particle with simple harmonic motion is __________ proportional to the angular velocity.

A. directly
B. inversely

18. The motion of a particle around a fixed axis is

A. translatory
B. rotary
C. circular
D. translatory as well as rotary 