Explore topic-wise MCQs in Engineering Mechanics.

This section includes 32 Mcqs, each offering curated multiple-choice questions to sharpen your Engineering Mechanics knowledge and support exam preparation. Choose a topic below to get started.

1.

The cable AO exerts a force on the top of the pole of F = {—120i — 90j — 80k} lb. If the cable has a length of 34 ft, determine the height z of the pole and the location (x,y) of its base.

A. x = 16 ft, y = 16 ft, z = 25 ft
B. x = 12 ft, y = 9 ft, z = 8 ft
C. x = 20 ft, y = 10 ft, z = 14 ft
D. x = 24 ft, y = 18 ft, z = 16 ft
Answer» E.
2.

The gusset plate G of a bridge joint is subjected to the two member forces at A and B. If the force at B is horizontal and the force at A is directed at = 30°, determine the magnitude and direction of the resultant force.

A. R = 458 N, = 97.5° CCW
B. R = 252 N, = 82.5° CCW
C. R = 252 N, = 97.5° CCW
D. R = 458 N, = 82.5° CCW
Answer» D. R = 458 N, = 82.5° CCW
3.

If = 20° and = 35°, determine the magnitudes of F1 and F2 so that the resultant force has a magnitude of 20 lb and is directed along the positive x axis.

A. F1 = 20.0 lb, F2 = 22.9 lb
B. F1 = 25.6 lb, F2 = 26.6 lb
C. F1 = 28.5 lb, F2 = 11.91 lb
D. F1 = 14.00 lb, F2 = 8.35 lb
Answer» E.
4.

Determine the design angle ( <90°) bretween the two struts so that the 500-lb horizontal force has a component of 600lb directed from A toward C. That is the component of force acting along member AB?

A. FAB = 321 lb, = 40.0°
B. FAB = 383 lb, = 36.9°
C. FAB = 171.1 lb, = 20.0°
D. FAB = 215 lb, = 52.7°
Answer» E.
5.

Determine the magnitude of the x and y components of the 2—kN force.

A. Fx = -1.414 kN, Fy = -1.414 kN
B. Fx = -1.000 kN, Fy = -1.732 kN
C. Fx = -1.732 kN, Fy = -1.000 kN
D. Fx = -4.000 kN, Fy = -2.312 kN
Answer» C. Fx = -1.732 kN, Fy = -1.000 kN
6.

Two forces act on a block. Determine the angle between them.

A. = 135.0°
B. = 65.1°
C. = 45.0°
D. = 114.9°
Answer» E.
7.

Determine the magnitude and direction angles of F2, so that the resultant of the two forces acts upward along the z axis of the pole and has a magnitude of 275 N.

A. F2 = 246 N, = 54.9°, = 114.0°, = 44.7°
B. F2 = 200 N, = 45.0°, = -60.0°, = 29.0°
C. F2 = 200 N, = 45.0°, = 120.0°, = 29.0°
D. F2 = 246 N, = 54.9°, = 66.0°, = 44.7°
Answer» B. F2 = 200 N, = 45.0¬∞, = -60.0¬∞, = 29.0¬∞
8.

If = 20° and = 35°, determine the magnitudes of F1 and F2 so that the resultant force has a magnitude of 20 lb and is directed along the positive x axis.

A. F1 = 20.0 lb, F2 = 22.9 lb
B. F1 = 25.6 lb, F2 = 26.6 lb
C. F1 = 28.5 lb, F2 = 11.91 lb
D. F1 = 14.00 lb, F2 = 8.35 lb
Answer» E.
9.

The antenna tower is supported by three cables. The forces in these cables are as follows: FB = 520 N, FC = 680 N, and FD = 560 N. Write the resultant of these three forces as a vector.

A. R = (4i +16j-72k) N
B. R = (-120i +40 j-960k) N
C. R = (560i +720j+1440k) N
D. R = (80i +320j-1440k) N
Answer» E.
10.

Determine the magnitudes of the resultant force and its direction measured from the positive x axis.

A. R = 12.49 kN, = 43.9° CW
B. R = 13.6 kN, = 21.5° CW
C. R = 14.00 kN, = 60.0° CW
D. R = 10.80 kN, = 68.2° CW
Answer» B. R = 13.6 kN, = 21.5¬∞ CW
11.

Cable BC exerts a force of F = 28 N on the top of the flagpole. Determine the projection of this force along the positive z axis of the pole.

A. F = 24 N
B. F = -24 N
C. F = 12 N
D. F = 12 N
Answer» C. F = 12 N
12.

The ball joint is subjected to the three forces shown. Find the magnitude of the resultant force.

A. R = 5.30 kN
B. R = 5.74 kN
C. R = 5.03 kN
D. R = 6.20 kN
Answer» E.
13.

Determine the design angle ( <90°) bretween the two struts so that the 500-lb horizontal force has a component of 600lb directed from A toward C. That is the component of force acting along member AB?

A. FAB = 321 lb, = 40.0°
B. FAB = 383 lb, = 36.9°
C. FAB = 171.1 lb, = 20.0°
D. FAB = 215 lb, = 52.7°
Answer» E.
14.

Determine the projection of the position vector r along the aa axis.

A. raa = 35.3 m
B. raa = 6.28 m
C. raa = 5.42 m
D. raa = 5.61 m
Answer» D. raa = 5.61 m
15.

Express the Force F2 in Cartesian vector form.

A. F2 = (155 i + 155 j + 300 k) lb
B. F2 = (212 i + 212 j - 519 k) lb
C. F2 = (155 i + 155 j - 300 k) lb
D. F2 = (367 i + 367 j - 300 k) lb
Answer» E.
16.

Determine the magnitude and direction of F so that this force has components of 40 lb acting from A toward B and 60lb acting from A toward C on the frame.

A. F = 44.7 lb, = 22.9°
B. F = 80.3 lb, = 46.2°
C. F = 62.9 lb, = 37.1°
D. F = 72.1 lb, = 56.3°
Answer» C. F = 62.9 lb, = 37.1¬∞
17.

Determine the design angle for connecting member A to the plate if the resultant force is to be directed vercially upward. Also, what is the magnitude of the resultant?

A. R = 400 N, = 53.5°
B. R = 250 N, = 30.0°
C. R = 300 N, = 36.9°
D. R = 640 N, = 38.6°
Answer» D. R = 640 N, = 38.6¬∞
18.

Determine the angle between the pole AC and the wire AB.

A. = 131.8°
B. = 70.5°
C. = 109.5°
D. = 48.2°
Answer» C. = 109.5¬∞
19.

Determine the magnitude of the x and y components of the 700-lb force.

A. Fx = -350 lb, Fy = 606 lb
B. Fx = -404 lb, Fy = 571 lb
C. Fx = -606 lb, Fy = 350 lb
D. Fx = -571 lb, Fy = 404 lb
Answer» D. Fx = -571 lb, Fy = 404 lb
20.

What is the projection of the force F2 along the positive axis?

A. F2y = 170.0 N
B. F2y = —80.0 N
C. F2y = 90.0 N
D. F2y = 120.0 N
Answer» D. F2y = 120.0 N
21.

The gusset plate G of a bridge joint is subjected to the two member forces at A and B. If the force at B is horizontal and the force at A is directed at = 30°, determine the magnitude and direction of the resultant force.

A. R = 458 N, = 97.5° CCW
B. R = 252 N, = 82.5° CCW
C. R = 252 N, = 97.5° CCW
D. R = 458 N, = 82.5° CCW
Answer» D. R = 458 N, = 82.5¬∞ CCW
22.

Determine the magnitude and direction of the position vector r which points from point A to point B.

A. r = 12 ft, = 70.5°, = 48.2°, = 131.8°
B. r = 12 ft, = 109.5°, = 131.8°, = 48.2°
C. r = 12 ft, = 70.5°, = 48.2°, = 48.2°
D. r = 12 ft, = 109.5°, = 131.8°, = 131.8°
Answer» B. r = 12 ft, = 109.5¬∞, = 131.8¬∞, = 48.2¬∞
23.

The cable AO exerts a force on the top of the pole of F = {—120i — 90j — 80k} lb. If the cable has a length of 34 ft, determine the height z of the pole and the location (x,y) of its base.

A. x = 16 ft, y = 16 ft, z = 25 ft
B. x = 12 ft, y = 9 ft, z = 8 ft
C. x = 20 ft, y = 10 ft, z = 14 ft
D. x = 24 ft, y = 18 ft, z = 16 ft
Answer» E.
24.

Determine the magnitude of the x and y components of the 2—kN force.

A. Fx = -1.414 kN, Fy = -1.414 kN
B. Fx = -1.000 kN, Fy = -1.732 kN
C. Fx = -1.732 kN, Fy = -1.000 kN
D. Fx = -4.000 kN, Fy = -2.312 kN
Answer» C. Fx = -1.732 kN, Fy = -1.000 kN
25.

Determine the magnitude of the resultant force by adding the rectangular components of the three forces.

A. R = 29.7 N
B. R = 54.2N
C. R = 90.8 N
D. R = 24.0 N
Answer» B. R = 54.2N
26.

Express force F as a Cartesian vector; then determine its direction angles.

A. F = (-2i +j+2k) kN, = 48.2°, = 70.5°, = 48.2°
B. F = (-2i +j+2k) kN, = 131.8°, = 70.5°, = 48.2°
C. F = (-4i +j+4k) kN, = 48.2°, = 70.5°, = 48.2°
D. F = (-4i +2j+4k) kN, = 131.8°, = 70.5°, = 48.2°
Answer» C. F = (-4i +j+4k) kN, = 48.2¬∞, = 70.5¬∞, = 48.2¬∞
27.

Determine the magnitude and direction of the resultant force.

A. R = 80.3 lb, = 106.2° CCW
B. R = 80.3 lb, = 73.8° CCW
C. R = 72.1 lb, = 63.6° CCW
D. R = 72.1 lb, = 116.4° CCW
Answer» B. R = 80.3 lb, = 73.8¬∞ CCW
28.

Express the force F1 in Cartesian vector form.

A. F1 = (200 i - 200 j + 283 k) lb
B. F1 = (200 i + 200 j + 283 k) lb
C. F1 = (-200 i + 200 j + 565 k) lb
D. F1 = (-200 i + 200 j + 283 k) lb
Answer» E.
29.

Force F acts on peg A such that one of its components, lying in the x-y plane, has a magnitude of 50 lb. Express F as a Cartesian vector.

A. F = (43.3 i + 25.0 j + 25.0 k) lb
B. F = (43.3 i + 25.0 j + 28.9 k) lb
C. F = (43.3 i - 25.0 j + 25.0 k) lb
D. F = (43.3 i - 25.0 j + 28.9 k) lb
Answer» E.
30.

If F1 = F2 = 30lb, determine the angles and so that the resultant force is directed along the positive x axis and has a magnitude of FR = 20 lb.

A. = = 70.5°
B. = = 41.4°
C. = = 19.47°
D. = = 18.43°
Answer» B. = = 41.4¬∞
31.

Express each force in Cartesian vector form.

A. F1 = (2.50 i + 3.54 j + 2.50 k) kN, F2 = -2 j kN
B. F1 = (4.33 i + 3.54 j + 4.33 k) kN, F2 = -2 j kN
C. F1 = (2.17 i + 3.75 j + 4.33 k) kN, F2 = -2 j kN
D. F1 = (4.33 i + 3.75 j + 2.17 k) kN, F2 = -2 j kN
Answer» B. F1 = (4.33 i + 3.54 j + 4.33 k) kN, F2 = -2 j kN
32.

The cord is attached between two walls. If it is 8 m long, determine the distance x to the point of attachment at B.

A. x = 7.75 m
B. x = 7.68 m
C. x = 6.93 m
D. x = 7.94 m
Answer» C. x = 6.93 m