Science test Flashcards
What is a projection?
A projection is a representation of a 3D object on a 2D surface.
What are the 2 projections that are used to represent an object in 3D?
Oblique and Isometric projections
In which projection are visual lines perpendicular to the paper?
Isometric projection
What does oblique mean?
Neither parallel nor at a right angle to a specified or implied line; slanting.
True or false:
Oblique and isometric projections are not 3D.
False
What’s a multiview projection?
A multiview projection is a 2D representation of one of the sides of an object.
What are the most necessary views to get an accurate representation of the details of an object?
Top, front, right side.
What view shows the various parts of the object separated from each other?
An exploded view.
What’s the function of an object line?
Shows visible details.
What’s the function of a hidden line?
It shows hidden detail.
What’s the function of a dimension line?
It shows a dimension.
What’s the function of an extension line?
It shows the start and the finish of measurement.
What’s the function of center and symmetry lines?
They show the center of a circle from the side view.
What’s a full size scale used for?
It’s used to show the actual measurements of the objects.
What’s a reduction scale used for?
It’s used to show a large object on a paper.
What’s an enlargement scale used for?
It’s used to show a small object on paper.
What would a full size scale look like?
1:1
What would a reduction scale look like?
1:2
What would an enlarged scale look like?
3:1
What’s tension?
A pulling force.
What’s compression?
A squeezing force.
What’s torsion?
A twisting force.
What’s deflection?
A bending force.
What’s Shearing?
A cutting force.
What does the property HARDNESS do?
It has the ability to resist denting or scratching.
What does the property RIGIDITY do?
It has the ability to resist deformation.
What does the property RESILIENCE do?
It has the ability to resist impact.
What does the property MALLEABILITY do?
It has the ability to be flattened into a sheet. (easily shape)
What does the property BRITTLENESS do?
It’s the opposite of resilience.
What does the property DUCTILITY do?
It has the ability to be stretched out into wire.
What does the property ELASTICITY do?
Ability to return to original shape.
What does the property ELECTRICAL CONDUCTIVITY do?
Allows an electrical current to flow. (Opposite: insulator)
What does the property THERMAL CONDUCTIVITY do?
It allows thermal energy through.
What does the property CORROSION RESISTANCE do?
Ability to resist rusting.
What are some examples of modified woods?
Particle board
Fiber board
Plywood
Explain what modified woods are.
Modified wood is a generic term that describes the application of chemical, physical, or biological methods that are used to alter the cellular structure of the wood.
What are the 2 types of woods?
Hardwood and softwood
What type of a tree is hardwood?
Deciduous trees because they are leafy. They are used to make floors and furniture.
What type of a tree is softwood?
Coniferous trees because they are evergreen and they are used outdoor for deck/furniture.
