# Engineering Mechanics – Section 6

11. A ladder is resting on a smooth ground and leaning against a rough vertical wall. The force of friction will act

A. towards the wall at its upper end
B. away from the wall at its upper end
C. downward at its upper end
D. upward at its upper end

Correct Answer: D. upward at its upper end

12. The length of a second’s pendulum is

A. 94.9cm
B. 99.4cm
C. 100cm
D. 101cm

13. The slope on the road surface generally provided on the curves is known as

A. angle of friction
B. angle of repose
C. angle of banking
D. none of these

Correct Answer: C. angle of banking

14. Coplanar non-concurrent forces are those forces which __________ at one point, but their lines of action lie on the same plane.

A. meet
B. do not meet

Correct Answer: B. do not meet

15. The moment of inertia of a rectangular section 3cm wide and 4cm deep about XX axis is

A. 9cm4
B. 12cm4
C. 16cm4
D. 20cm4

16. A pendulum which executes one beat per second is known as

A. simple pendulum
B. compound pendulum
C. torsional pendulum
D. second’s pendulum

17. Two blocks A and B of masses 150 kg and 50 kg respectively are connected by means of a string as shown in the below figure. The tension in all the three strings __________ be same.

A. will
B. will not

18. D’ Alembert’s principle basically depends upon Newton’s second law of motion.

A. Correct
B. Incorrect

19. The forces, whose lines of action are parallel to each other and act in the same directions, are known as

A. coplanar concurrent forces
B. coplanar non-concurrent forces
C. like parallel forces
D. unlike parallel forces

Correct Answer: C. like parallel forces

20. A number of forces acting at a point will be in equilibrium, if

A. all the forces are equally inclined
B. sum of all the forces is zero
C. sum of resolved parts in the vertical direction is zero (i.e. ∑V = 0)
D. none of these

Correct Answer: C. sum of resolved parts in the vertical direction is zero (i.e. ∑V = 0)