PSE 212 FINAL EXAM QUESTIONS AND ANSWERS
This sample holder is used in what paper test? (round circle) - CORRECT ANSWER✅✅✅Ring crush
Match the "paper term" for the corresponding term used in engineering or material science. - CORRECT
ANSWER✅✅✅Tensile Stiffness-> Elastic Modulus
Force -> Stress
Tensile Strength -> Ultimate Stress
% Elongation- Strain
Tensile Energy Absorption-> TEA
You are getting ready to make a presentation to a group of co-workers. It is important to report your
findings in an accurate manner. You measured the water absorption of 10 different samples and got a
result of 12.3 g/g for water uptake. The Sample standard deviation is 4.6 g/g. Determine the value for
the blank below at a 90 % Confidence interval. - CORRECT ANSWER✅✅✅2.67
A solid surface has an inter-facial surface energy of 62.3 J/m^2 when exposed to a vapor. A liquid is
applied to the surface and it has an inter-facial surface energy of 22.8 J/m^2 when exposed to the same
vapor as the solid. The contact angle formed is 23 degrees. What is the inter-facial surface energy of the
liquid/solid interface in J/m^2? - CORRECT ANSWER✅✅✅41.31
You are trying to determine if a property of two different samples is statically different. For the first
sample you measure the property 5 times. For the second sample you measure the property 9 times.
When determining the t-score to be used, what degree of freedom should you use? - CORRECT
ANSWER✅✅✅4
As more fibers become oriented in the machine direction, we expect the tensile strength to increase due
to the increased basis weight uniformity. - CORRECT ANSWER✅✅✅False
You are trying to determine the formation of a tissue sheet with a grammage of 40. You have an
inspection areas of 1 mm^2. You determine that there are 100 fibers per square millimeter on average.
What formation index (FI) would you calculate with an inspection area of 1 mm^2? - CORRECT
ANSWER✅✅✅0.1
, The piece of equipment pictured below measure which properties.(tissue machine in back corner) -
CORRECT ANSWER✅✅✅Softness and ball burst
A hardwood (HW) and softwood (SW) fiber are mixed together at a mass fraction of 0.5 HW and 0.5 SW.
The average fiber length for the HW is 1 mm and for the SW 2 mm. Which of the following values for
average length for the mixture you would NOT expect to see? - CORRECT ANSWER✅✅✅1.5mm
These types of bonds are credited with giving paper its strength. - CORRECT
ANSWER✅✅✅Hydrogen Bonds
A papermaker has a increase the moisture content of the sheet. He see a higher tear strength and
decreased tensile strength. What adjustment should he make to resolve this issue? - CORRECT
ANSWER✅✅✅increase drying
A paper sheet weighs 1.20 grams. It has an area of 0.02 meters squared. What is the basis weight in
units of grams per meter square? - CORRECT ANSWER✅✅✅60g/m^2
The opening in the center of a wood fiber is called: - CORRECT ANSWER✅✅✅Lumen
As beating continues, the freeness ________. - CORRECT ANSWER✅✅✅Goes down.
Which type of wood cell is not found in a softwood tree? - CORRECT ANSWER✅✅✅Vessel Element
In a refiner, the long axis (axial direction) of the fiber is oriented in which direction to the shearing action
of the refiner? - CORRECT ANSWER✅✅✅Perpendicular
The best way to increase tear and tensile strength is to add softwood fiber to paper. - CORRECT
ANSWER✅✅✅true
What chemical is represented by the letter E in a D-E-D-E-D bleaching sequence? - CORRECT
ANSWER✅✅✅Sodium hydroxide
This sample holder is used in what paper test? (round circle) - CORRECT ANSWER✅✅✅Ring crush
Match the "paper term" for the corresponding term used in engineering or material science. - CORRECT
ANSWER✅✅✅Tensile Stiffness-> Elastic Modulus
Force -> Stress
Tensile Strength -> Ultimate Stress
% Elongation- Strain
Tensile Energy Absorption-> TEA
You are getting ready to make a presentation to a group of co-workers. It is important to report your
findings in an accurate manner. You measured the water absorption of 10 different samples and got a
result of 12.3 g/g for water uptake. The Sample standard deviation is 4.6 g/g. Determine the value for
the blank below at a 90 % Confidence interval. - CORRECT ANSWER✅✅✅2.67
A solid surface has an inter-facial surface energy of 62.3 J/m^2 when exposed to a vapor. A liquid is
applied to the surface and it has an inter-facial surface energy of 22.8 J/m^2 when exposed to the same
vapor as the solid. The contact angle formed is 23 degrees. What is the inter-facial surface energy of the
liquid/solid interface in J/m^2? - CORRECT ANSWER✅✅✅41.31
You are trying to determine if a property of two different samples is statically different. For the first
sample you measure the property 5 times. For the second sample you measure the property 9 times.
When determining the t-score to be used, what degree of freedom should you use? - CORRECT
ANSWER✅✅✅4
As more fibers become oriented in the machine direction, we expect the tensile strength to increase due
to the increased basis weight uniformity. - CORRECT ANSWER✅✅✅False
You are trying to determine the formation of a tissue sheet with a grammage of 40. You have an
inspection areas of 1 mm^2. You determine that there are 100 fibers per square millimeter on average.
What formation index (FI) would you calculate with an inspection area of 1 mm^2? - CORRECT
ANSWER✅✅✅0.1
, The piece of equipment pictured below measure which properties.(tissue machine in back corner) -
CORRECT ANSWER✅✅✅Softness and ball burst
A hardwood (HW) and softwood (SW) fiber are mixed together at a mass fraction of 0.5 HW and 0.5 SW.
The average fiber length for the HW is 1 mm and for the SW 2 mm. Which of the following values for
average length for the mixture you would NOT expect to see? - CORRECT ANSWER✅✅✅1.5mm
These types of bonds are credited with giving paper its strength. - CORRECT
ANSWER✅✅✅Hydrogen Bonds
A papermaker has a increase the moisture content of the sheet. He see a higher tear strength and
decreased tensile strength. What adjustment should he make to resolve this issue? - CORRECT
ANSWER✅✅✅increase drying
A paper sheet weighs 1.20 grams. It has an area of 0.02 meters squared. What is the basis weight in
units of grams per meter square? - CORRECT ANSWER✅✅✅60g/m^2
The opening in the center of a wood fiber is called: - CORRECT ANSWER✅✅✅Lumen
As beating continues, the freeness ________. - CORRECT ANSWER✅✅✅Goes down.
Which type of wood cell is not found in a softwood tree? - CORRECT ANSWER✅✅✅Vessel Element
In a refiner, the long axis (axial direction) of the fiber is oriented in which direction to the shearing action
of the refiner? - CORRECT ANSWER✅✅✅Perpendicular
The best way to increase tear and tensile strength is to add softwood fiber to paper. - CORRECT
ANSWER✅✅✅true
What chemical is represented by the letter E in a D-E-D-E-D bleaching sequence? - CORRECT
ANSWER✅✅✅Sodium hydroxide
