EXTRUDE command for 3D from 2D in AutoCAD - Cell-by-Cell Formula Trace

Sample Data

This table shows 2D shapes with their extrusion heights. The goal is to calculate the volume of the 3D shape created by extruding the 2D shape by the given height.

Cell	Value
A1	Shape
B1	Height
C1	Volume
A2	Rectangle 5x3
B2	4
C2
A3	Circle radius 2
B3	6
C3

Formula Trace

Volume = Area_of_2D_shape * Height

Step 1: Area_of_2D_shape for Rectangle 5x3 = 5 * 3

Step 2: Volume for Rectangle = 15 * 4 (height)

Step 3: Area_of_2D_shape for Circle radius 2 = π * 2^2

Step 4: Volume for Circle = 12.5664 * 6 (height)

Cell Reference Map

   A           B       C
1 Shape      Height  Volume
2 Rectangle 5x3  4       
3 Circle radius 2    6       

Cells A2 and B2 are used to calculate volume in C2. Cells A3 and B3 are used to calculate volume in C3.

Result

   A           B       C
1 Shape      Height  Volume
2 Rectangle 5x3  4      60
3 Circle radius 2    6    75.3984

The volume column shows the result of extruding the 2D shape by the height. Rectangle volume is 60 cubic units, Circle volume is approximately 75.4 cubic units.

Sheet Trace Quiz - 3 Questions

What is the area of the rectangle before extrusion?

A 15

B 20

C 12

D 8

Key Result

Volume = Area_of_2D_shape * Extrusion_Height

Practice

1. What does the EXTRUDE command do in AutoCAD?

easy

A. It colors 2D shapes with different shades.

B. It converts 3D objects back to 2D shapes.

C. It deletes 2D shapes from the drawing.

D. It turns 2D shapes into 3D objects by adding height.

Solution

1. Step 1: Understand the purpose of EXTRUDE

   The EXTRUDE command is used to add height or thickness to flat 2D shapes.

2. Step 2: Identify the effect on 2D shapes

   By stretching the 2D shape vertically, it becomes a 3D object.

3. Final Answer:

   It turns 2D shapes into 3D objects by adding height. -> Option D

4. Quick Check:

   EXTRUDE adds height to 2D shapes [OK]

Hint: EXTRUDE adds height to flat shapes to make 3D [OK]

Common Mistakes:

• Thinking EXTRUDE changes color
• Confusing EXTRUDE with deleting shapes
• Believing EXTRUDE flattens 3D objects

2. Which of the following is the correct syntax to start the EXTRUDE command in AutoCAD?

easy

A. Type EXTRUDE and press Enter

B. Type EXTRUDE3D and press Enter

C. Type EXTRUDE2D and press Enter

D. Type EXTRUDE_SHAPE and press Enter

Solution

1. Step 1: Recall the command name

   The correct command to extrude shapes in AutoCAD is EXTRUDE.

2. Step 2: Confirm the syntax to start the command

   Typing EXTRUDE and pressing Enter activates the command.

3. Final Answer:

   Type EXTRUDE and press Enter -> Option A

4. Quick Check:

   EXTRUDE command starts with 'EXTRUDE' [OK]

Hint: Start EXTRUDE by typing 'EXTRUDE' then Enter [OK]

Common Mistakes:

• Using incorrect command names like EXTRUDE3D
• Adding extra suffixes to the command
• Confusing with other 3D commands

3. Given a closed 2D circle with radius 5 units, what will be the height of the 3D cylinder after running EXTRUDE with a height value of 10 units?

medium

A. 10 units

B. 5 units

C. 15 units

D. 50 units

Solution

1. Step 1: Understand the input shape and extrusion height

   The 2D shape is a circle with radius 5 units. The extrusion height given is 10 units.

2. Step 2: Determine the resulting 3D object's height

   The EXTRUDE command adds the specified height (10 units) vertically to the shape, creating a cylinder of height 10 units.

3. Final Answer:

   10 units -> Option A

4. Quick Check:

   Extrusion height = 10 units [OK]

Hint: Extrusion height equals the input height value [OK]

Common Mistakes:

• Confusing radius with extrusion height
• Adding radius and height incorrectly
• Assuming extrusion multiplies dimensions

4. You tried to extrude a 2D open polyline but got an error. What is the most likely cause?

medium

A. You used the wrong command name.

B. The extrusion height was set to zero.

C. The polyline is not closed, so extrusion is not possible.

D. The 2D shape is already 3D.

Solution

1. Step 1: Understand extrusion requirements

   EXTRUDE requires closed 2D shapes to create 3D solids.

2. Step 2: Identify the problem with an open polyline

   An open polyline is not closed, so AutoCAD cannot extrude it into a solid.

3. Final Answer:

   The polyline is not closed, so extrusion is not possible. -> Option C

4. Quick Check:

   Closed shape needed for extrusion [OK]

Hint: Ensure shape is closed before extruding [OK]

Common Mistakes:

• Trying to extrude open shapes
• Ignoring extrusion height value
• Using wrong command names

5. You have a 2D rectangle with length 8 units and width 4 units. You want to create a 3D box with volume 192 cubic units using the EXTRUDE command. What extrusion height should you enter?

hard

A. 24 units

B. 6 units

C. 12 units

D. 48 units

Solution

1. Step 1: Calculate base area of the rectangle

   Area = length x width = 8 x 4 = 32 square units.

2. Step 2: Use volume formula to find extrusion height

   Volume = base area x height. So, height = Volume ÷ base area = 192 ÷ 32 = 6 units.

3. Final Answer:

   6 units -> Option B

4. Quick Check:

   Height = Volume / Area = 6 units [OK]

Hint: Divide volume by base area to get extrusion height [OK]

Common Mistakes:

• Multiplying instead of dividing for height
• Using length or width as height
• Ignoring units in calculation