READING QUIZ

1. One of the assumptions used when analyzing a simple truss is that

the members are joined together by __________.

A) Welding B) Bolting C) Riveting

D) Smooth pins E) Super glue

2. When using the method of joints, typically _________ equations of

equilibrium are applied at every joint.

A) Two B) Three

C) Four D) Six

CONCEPT QUIZ

1. Truss ABC is changed by decreasing its

height from H to 0.9 H. Width W and load

P are kept the same. Which one of the

following statements is true for the revised

truss as compared to the original truss?

A) Force in all its members have decreased.

B) Force in all its members have increased.

C) Force in all its members have remained

the same.

D) None of the above.

H

P

A

B C

W

CONCEPT QUIZ

(continued)

2. For this truss, determine the number of zero-force

members.

A) 0 B) 1 C) 2

D) 3 E) 4

F F

F

ATTENTION QUIZ

1. Using this FBD, you find that FBC = – 500 N.

Member BC must be in __________.

A) Tension

B) Compression

C) Cannot be determined

2. For the same magnitude of force to be

carried, truss members in compression

are generally made _______ as compared

to members in tension.

A) Thicker

B) Thinner

C) The same size

FBD

FBC

B

BY

READING QUIZ

1. In the method of sections, generally a “cut” passes through no

more than _____ members in which the forces are unknown.

A) 1 B) 2

C) 3 D) 4

2. If a simple truss member carries a tensile force of T along its

length, then the internal force in the member is ______ .

A) Tensile with magnitude of T/2

B) Compressive with magnitude of T/2

C) Compressive with magnitude of T

D) Tensile with magnitude of T

CONCEPT QUIZ

1. Can you determine the force in

member ED by making the cut

at section a-a? Explain your

answer.

A) No, there are 4 unknowns.

B) Yes, using MD = 0 .

C) Yes, using ME = 0 .

D) Yes, using MB = 0 .

CONCEPT QUIZ

2. If you know FED, how will you determine FEB ?

A) By taking section b-b and using ME = 0

B) By taking section b-b, and using FX = 0 and FY = 0

C) By taking section a-a and using MB = 0

D) By taking section a-a and using MD = 0

ATTENTION QUIZ

1. As shown, a cut is made

through members GH, BG

and BC to determine the

forces in them. Which section

will you choose for analysis

and why?

A) Right, fewer calculations.

B) Left, fewer calculations.

C) Either right or left, same

amount of work.

D) None of the above, too

many unknowns.

ATTENTION QUIZ

2. When determining the force in

member HG in the previous

question, which one equation of

equilibrium is best to use?

A) MH = 0

B) MG = 0

C) MB = 0

D) MC = 0

READING QUIZ

1. Frames and machines are different as compared to trusses since they

have ___________.

A) Only two-force members B) Only multiforce members

C) At least one multiforce member D) At least one two-force

member

2. Forces common to any two contacting members act with _______

on the other member.

A) Equal magnitudes but opposite sense

B) Equal magnitudes and the same sense

C) Different magnitudes but opposite sense

D) Different magnitudes but the same sense

CONCEPT QUIZ

1. The figures show a frame and its FBDs. If an additional couple

moment is applied at C, then how will you change the FBD of

member BC at B?

A) No change, still just one force (FAB) at B.

B) Will have two forces, BX and BY, at B.

C) Will have two forces and a moment at B.

D) Will add one moment at B.

2. The figures show a frame and its FBDs. If an additional force is

applied at D, then how will you change the FBD of member BC

at B?

A) No change, still just one force (FAB) at B.

B) Will have two forces, BX and BY, at B.

C) Will have two forces and a moment at B.

D) Will add one moment at B.

CONCEPT QUIZ (continued)

D

ATTENTION QUIZ

2. For the above problem, imagine that you have drawn a FBD

of member AB. What will be the easiest way to write an

equation involving unknowns at B?

A) MC = 0 B) MB = 0

C) MA = 0 D) FX = 0

1. When determining the reactions

at joints A, B, and C, what is the

minimum number of unknowns

for solving this problem?

A) 3 B) 4

C) 5 D) 6

READING QUIZ

1. A friction force always acts _____ to the contact surface.

A) Normal B) At 45°

C) Parallel D) At the angle of static friction

2. If a block is stationary, then the friction force acting on it is

________ .

A) s N B) = s N

C) s N D) = k N

CONCEPT QUIZ

1. A 100 lb box with a wide base is pulled by a force P

and s = 0.4. Which force orientation requires the

least force to begin sliding?

A) P(A) B) P(B)

C) P(C) D) Can not be determined

P(A)

P(B)

P(C) 100 lb

2. A ladder is positioned as shown. Please indicate

the direction of the friction force on the ladder at

B.

A) B)

C) D)

A

B

ATTENTION QUIZ

2. The ladder AB is postioned as shown. What is the

direction of the friction force on the ladder at B.

A) B)

C) D) A

B

1. A 10 lb block is in equilibrium. What is

the magnitude of the friction force

between this block and the surface?

A) 0 lb B) 1 lb

C) 2 lb D) 3 lb

S = 0.3

2 lb

READING QUIZ

1. A wedge allows a ______ force P to lift

a _________ weight W.

A) (large, large) B) (small, small)

C) (small, large) D) (large, small)

2. Considering friction forces and the

indicated motion of the belt, how are belt

tensions T1 and T2 related?

A) T1 > T2 B) T1 = T2

C) T1 < T2 D) T1 = T2 e

W

CONCEPT QUIZ

2. The boy (hanging) in the picture weighs

100 lb and the woman weighs 150 lb. The

coefficient of static friction between her

shoes and the ground is 0.6. The boy will

______ ?

A) Be lifted up B) Slide down

C) Not be lifted up D) Not slide down

1. Determine the direction of the friction

force on object B at the contact point

between A and B.

A) B)

C) D)

ATTENTION QUIZ

2. In the analysis of frictional forces on a flat belt, T2 = T1 e .

In this equation, equals ______ .

A) Angle of contact in degrees B) Angle of contact in radians

C) Coefficient of static friction D) Coefficient of kinetic friction

1. When determining the force P needed to lift the

block of weight W, it is easier to draw a FBD

of ______ first.

A) The wedge B) The block

C) The horizontal ground D) The vertical wall

W

READING QUIZ

1. A screw allows a ______ moment M to

lift a _________ weight W.

A) (large, large) B) (small, small)

C) (small, large) D) (large, small)

2. A screw is self locking if it remains in

place under __________ loads.

A) any axial B) small axial

C) any rotational D) small rotational

W