#1
Which of the following is an example of a common adhesive used in households?
Super glue
ExplanationSuper glue is a widely used adhesive in households for its quick bonding properties and versatility.
#2
What type of force is responsible for adhesion?
Electrostatic force
ExplanationAdhesion is primarily driven by electrostatic forces that attract molecules of the adhesive and substrate.
#3
Which of the following is NOT a factor influencing the strength of adhesion?
Inertia
ExplanationInertia is not a factor influencing adhesion strength; factors include surface preparation, chemistry, and contact time.
#4
What is the phenomenon called when an adhesive fails to stick to a surface due to the presence of air pockets?
Cavitation
ExplanationCavitation occurs when air pockets prevent proper contact between the adhesive and the substrate, leading to bond failure.
#5
What is the phenomenon where an adhesive bond weakens due to exposure to external factors such as heat, moisture, or chemicals?
Degradation
ExplanationDegradation refers to the weakening of an adhesive bond when exposed to external factors like heat, moisture, or chemicals.
#6
Which type of adhesive provides a strong bond quickly but requires tight fitting surfaces and cannot fill gaps?
Contact adhesives
ExplanationContact adhesives offer fast bonding, but they require tight fits and lack gap-filling capabilities.
#7
What is the process of surface preparation that involves creating microscopic pores to enhance adhesion called?
Etching
ExplanationEtching is a surface preparation process that creates microscopic pores, enhancing the adhesive's ability to bond.
#8
Which type of adhesive would be most suitable for joining materials with different coefficients of thermal expansion?
Polyurethane adhesives
ExplanationPolyurethane adhesives are suitable for materials with different thermal expansion rates, providing flexibility and strength.
#9
Which of the following is NOT a type of failure mode in adhesively bonded joints?
Tensile failure
ExplanationTensile failure is not a typical failure mode; common modes include cohesive, adhesive, and compressive failures.
#10
What property of an adhesive indicates its ability to maintain its properties over time when subjected to external conditions?
Durability
ExplanationDurability is the property indicating an adhesive's ability to maintain its qualities over time despite exposure to external conditions.
#11
What is the term used to describe the process of an adhesive becoming solid or hard after application?
Curing
ExplanationCuring is the process where an adhesive solidifies or hardens after application, forming a strong bond.
#12
Which type of adhesive is known for its ability to withstand extreme temperatures and environmental conditions?
Hot melt adhesives
ExplanationHot melt adhesives are recognized for their resilience in extreme temperatures and harsh environmental conditions.