.q 1 0
Fiber volume fraction is defined as
.
.a a.	Volume of Fibers/Volume of Matrix.
.a b.	Volume of Fibers/Volume of Composite.
.a c.	1 plus the Matrix Volume Fraction.
.a d.	Volume of Composite/Volume of Fibers
.A 2
.R
The fiber volume fraction is the defined as the volume of fibers divided by the volume of the composite
.

.q 2 0
The change of properties for a corresponding 1 percent increase in void content is in the range of
.
.a a.	2 to 10 percent.
.a b.	less than 2 percent.
.a c.	2 to 15 percent.
.a d.	greater than 15 percent.
.A 1
.R
The change of properties for a corresponding 1 percent increase in void content is in the range of 2 to 10 percent
.

.q 3 0
The maximum fiber volume fraction for circular fibers in a square array is
.
.a a.	70.23 percent.
.a b.	90.69 percent.
.a c.	78.54 percent.
.a d.	86.93 percent.
.A 3
.R
The maximum fiber volume fraction for circular fibers in a square array is 78.54 percent
.

.q 4 0
The maximum fiber volume fraction for circular fibers in a hexagonal array is
.
.a a.	78.54 percent.
.a b.	90.69 percent.
.a c.	70.23 percent.
.a d.	86.93 percent.
.A 2
.R
The maximum fiber volume fraction for circular fibers in a hexagonal array is 90.69 percent
.

.q 5 0
Concerning the Halphin-Tsai equations for transverse elastic modulus, the reinforcing factor depends on
.
.a a.	Young's modulus of the fibers.
.a b.	Young's modulus of the matrix.
.a c.	fiber volume fraction.
.a d.	packing geometry.
.A 4
.R
Concerning the Halphin-Tsai equations for transverse elastic modulus, the reinforcing factor depends on the packing geometry
.

.q 6 0
The volume fraction of voids is generally determined by
.
.a a.	burn or acid digestion tests.
.a b.	tension tests.
.a c.	impact tests.
.a d.	purely analytical means.
.A 1
.R
The volume fraction of voids is generally determined by burn or acid digestion tests
.

.q 7 0
Volume fraction of voids is given by
.
.a a.	(theoretical minus experimental composite density)/theoretical composite density.
.a b.	(theoretical minus experimental composite density)/experimental composite density.
.a c.	void volume/(fiber volume plus composite volume).
.a d.	(experimental minus theoretical composite density)/experimental composite density.
.A 1
.R
Volume fraction of voids is given by the (theoretical minus experimental composite density)/experimental composite density 
.

.q 8 0
In a ceramic matrix material, generally matrix breaks precede fiber breaks
.
.a a.	True.
.a b.	False.
.A 1
.R
In a ceramic matrix material, generally matrix breaks precede fiber breaks
.

.q 9 0
The longitudinal modulus of a lamina is dependent on
.
.a a.	fiber Young's modulus.
.a b.	matrix Young's modulus.
.a c.	fiber volume fraction.
.a d.	all of the above.
.A 4
.R
The longitudinal modulus of a lamina is dependent on fiber Young's modulus, matrix Young's modulus, and the fiber volume fraction
.

.q 10 0
Longitudinal modulus of a lamina is greater than
.
.a a.	fiber and matrix Young's modulus.
.a b.	matrix Young's modulus if it is less than the fiber Young's modulus.
.a c.	fiber Young's modulus if it is greater than the matrix Young's modulus.
.A 
.R

.

.q 11 0
Generally for polymer matrix composites, the maximum strain to failure is greater for
.
.a a.	the fiber.
.a b.	the matrix.
.a c.	they are equal.
.A 2
.R
Generally for polymer matrix composites, the maximum strain to failure is greater for the matrix
.

.q 12 0
Unidirectional composites are tested because
.
.a a.	they are easy to manufacture.
.a b.	they are used in most applications.
.a c.	the results can be directly used to predict behavior in an off-axis lamina.
.A 3
.R
Unidirectional composites are tested because the results can be directly used to predict behavior in an off-axis lamina and multidirectional laminates.
.

.q 13 0
If the applied stress is greater than the longitudinal tensile strength, for which volume fraction of fibers is it possible for the composite to take a greater load?
.
.a a.	critical fiber volume fraction.
.a b.	minimum fiber volume fraction.
.a c.	maximum fiber volume fraction.
.A 2
.R
The minimum volume fraction
.

.q 14 0
Poor bonding between the fiber and matrix results in
.
.a a.	a decrease in the composite transverse strength.
.a b.	an increase in the composite transverse strength.
.a c.	no change in the composite transverse strength.
.A 1
.R
Poor bonding between the fiber and matrix results in a decrease in the composite transverse strength
.

.q 15 0
For a lamina exposed to changes in temperature, it is generally assumed that
.
.a a.	the change in temperature is the same for the fiber and the matrix.
.a b.	the change in temperature is greater in the matrix than in the fiber.
.a c.	the change in temperature is greater in the fiber than in the matrix.
.A 1
.R
For a lamina exposed to changes in temperature, it is generally assumed that the change in temperature is the same for the fiber and the matrix
.

.q 16 0
For polymeric composites exposed to a change in moisture, the moisture concentration in the fibers is generally
.
.a a.	greater than zero.
.a b.	less than zero.
.a c.	close to zero.
.A 3
.R
For polymeric composites exposed to a change in moisture, the moisture concentration in the fibers is generally close to zero
.

.q 17 0
For composites with high fiber to matrix moduli ratios, the longitudinal coefficient of moisture expansion is
.
.a a.	greater than the transverse value.
.a b.	less than the transverse value.
.a c.	equal to the transverse value.
.a d.	zero.
.A 4
.R
For composites with high fiber to matrix moduli ratios, the longitudinal coefficient of moisture expansion is zero
.

.q 18 0
The three most common types of fibers used in composites are glass, aramids, and graphite.  Of these, which are transversely isotropic?
.
.a a.	glass and graphite.
.a b.	glass and aramids.
.a c.	aramids and graphite.
.A 3
.
.R
The three most common types of fibers used in composites are glass, aramids, and graphite.  Of these, aramids and graphite are transversely isotropic

.

.q 19 0
For a composite under a transverse tensile load, a weak fiber-matrix bond
.
.a a.	may decrease the longitudinal tensile strength.
.a b.	may increase the longitudinal tensile strength.
.a c.	has no effect on the longitudinal tensile strength.
.A 2
.R
For a composite under a transverse tensile load, a weak fiber-matrix bond may increase the longitudinal tensile strength
.

.q 20 0
The component in a polymeric matrix component which carries the largest percentage of the applied load is
.
.a a.	the fibers.
.a b.	the matrix.
.a c.	Neither, the fiber and matrix share the load equally.
.A 1
.R
The component in a polymeric matrix component which carries the largest percentage of the applied load is the fibers
.

.q 21 0
Adding more fibers to a matrix
.
.a a.	increases the ultimate tensile strength of the composite compared to the matrix.
.a b.	decreases the ultimate tensile strength of the composite compared to the matrix.
.a c.	has no effect.
.A 2
.R
Adding fibers to a matrix decreases the ultimate tensile strength of the composite compared to the matrix
.

.q 22 2
What do you think of this test?
.
.a 8 60
.A kaw@eng.usf.edu