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WorksheetsRECF Manufacturing Technology
Total questions: 26
Worksheet time: 13mins
Which step in plastic injection molding ensures that the molten material fills the mold cavity under pressure?
A. Plastification
B. Packing
C. Demold
D. Ejection
In sand casting, which step determines the dimensional accuracy of the final part?
Gating system design
Cooling rate
Sand grain size
Pattern removal
Which of the following is a key advantage of FDM 3D printing over SLS?
Stronger interlayer bonding
Greater dimensional accuracy
Lower operating temperature
Use of metal powders
In selective laser sintering (SLS), what role does the laser play?
Trimming excess material
Initiating layer fusion
Heating the build plate
Cleaning the print bed
CNC milling relies on what type of coordinate movement system for precise part shaping?
Linear
Cartesian
Polar
Spherical
Which material property allows CNC water jet cutting to work on virtually any material?
Hardness
Density
Thermal conductivity
Electrical conductivity
CNC plasma cutting is most suitable for which of the following materials?
Plastics
Ceramics
Electrically conductive metals
Composites
Which best describes the cutting action in a lathe?
Cutter rotates around fixed material
Tool vibrates against stationary stock
Material rotates against a stationary cutter
Tool oscillates linearly
Orthographic projection is essential because it...
Shows real-time 3D rendering
Projects depth using perspective
Accurately represents each face of an object
Eliminates hidden lines
A scale factor of 0.25 on a drawing means...
Drawing is four times larger
Drawing is actual size
Drawing is one-fourth size
Drawing is scaled in inches
Auxiliary projection is most often used to...
Show hidden internal features
Provide an alternate angle view not on primary planes
Enhance 3D rendering
Indicate exploded views
Isometric projection differs from perspective drawing by...
Using converging lines
Not using scaling
Displaying equal angles between axes
Hiding depth
13. Which equation defines engineering strain?
Engineering strain = (Change in length) / (Original length)
Engineering strain = (Original length) / (Change in length)
Engineering strain = (Change in length) * (Original length)
Engineering strain = (Original length) - (Change in length)
Which type of stress results in torsion on a structural element?
Shear
Bending
Twisting moment
Compressive
The main purpose of a tensile test is to determine...
Melting point
Hardness
Load-bearing capacity before failure
Resistance to vibration
In the Rockwell hardness test, hardness is determined by...
Force to fracture
Depth of indentation
Modulus of elasticity
Electrical conductivity
Which property is true of thermoplastics?
They cure once and cannot be remelted
They conduct electricity
They can be reshaped by reheating
They decompose under UV light
What distinguishes thermosets from thermoplastics?
A. They are more flexible
B. They harden permanently after curing
C. They melt at lower temperatures
D. They are recyclable
In a stress-strain curve, the necking region occurs...
Before the elastic limit
Between yield and ultimate strength
Between ultimate strength and fracture
Immediately after loading
Stress is defined as...
Force divided by area
Change in length divided by original length
Load multiplied by distance
Stress divided by modulus
Strain is represented on which axis of a stress-strain graph?
Vertical
Diagonal
Horizontal
It is not plotted
Fracture point on a stress-strain graph represents...
Beginning of deformation
Point of maximum stress
Point of permanent damage
Failure of the material
Strain hardening improves material strength by...
Reducing thermal conductivity
Realigning crystalline structure under stress
Eliminating voids
Heating then cooling rapidly
The initial yield point is best defined as...
The moment the material fractures
The start of elastic deformation
The limit of elastic behavior before plastic deformation
The start of necking
Ultimate strength is the point where...
A. A material first stretches
B. Stress is the highest before fracture
C. Strain is irreversible
D. Load equals stress
The eutectic point describes...
The lowest temp at which solid and liquid phases coexist
The point where plastic begins to cure
The melting point of a metal
The yield strength under pressure
