# Engineering Mechanics – Section 4

21. The centre of gravity of a right angled triangle lies at its geometrical centre.

A. Correct
B. Incorrect

22. Vectors method for the resultant force is also called polygon law of forces.

A. Correct
B. Incorrect

23. Two equal and opposite parallel forces whose lines of action are different form a couple.

A. Correct
B. Incorrect

24. When a person, on a bicycle, drives round a curve, he has to lean __________ to maintain equilibrium.

A. inward
B. outward

25. A circular hole of 50 mm diameter is cut out from a circular disc of 100 mm diameter as shown in the below figure. The centre of gravity of the section will lie

B. in the hole
C. at O

26. The maximum velocity of a particle moving with simple harmonic motion is

A. ω
B. ωr
C. ω2r
D. ω/r

27. The loss of kinetic energy due to the direct impact of two bodies __________ upon the value of the coefficient of restitution.

A. depends
B. does not depend

28. A body of mass m moving with a constant velocity v strikes another body of same mass m moving with the same velocity but in opposite direction. The common velocity of both the bodies after the collision is

A. v
B. 2v
C. 4v
D. 8v