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