Deck 24: First-Angle Projection and Dimensioning

Question 1

Explain dimensioning on first-angle drawings.

Answer 1

Dimensions on first-angle drawings are in metric units of measure. When a numerical value is less than 1, the first numeral is preceded by a zero and a decimal point. For example, the decimal .733 is dimensioned to read 0.733. Whole numbers do not require a zero to the right of the decimal point. Twenty-four (24 mm) would not be written as 24.0; it would be 24 mm.

Question 2

The accepted standard of projection of the Common Market and other countries of the world relates to the ____ quadrant.

A) first
B) second
C) third
D) fourth

Answer 2

A

Question 3

In the accompanying figure, the item identified as number 1 represents the ____.

A) y-axis
B) x-axis
C) primary quadrant
D) secondary quadrant

Answer 3

A

Question 4

In the accompanying figure, the item identified as number 2 represents the ____.

A) y-axis
B) x-axis
C) vertical plane
D) horizontal plane

Question 5

In the accompanying figure, the item identified as number 3 represents the ____.

A) y-axis
B) x-axis
C) vertical plane
D) horizontal plane

Question 6

In first-angle projection, where is the left-side view drawn?

Question 7

In the accompanying figure, the item identified as number 4 represents the ____.

A) y-axis
B) x-axis
C) primary quadrant
D) secondary quadrant

Question 8

Explain why the third quadrant was adopted for project in the United States and Canada.

Question 9

Explain where the top view is in first-angle projection in contrast with third-angle projection.

Question 10

Explain how third-angle projection is derived.