Radius and diameter dimension in AutoCAD - Cell-by-Cell Formula Trace

Sample Data

This table shows circles with their radius values. The diameter column is empty and will be calculated as twice the radius.

Cell	Value
A1	Circle ID
B1	Radius
C1	Diameter
A2	Circle 1
B2	5
C2
A3	Circle 2
B3	7
C3
A4	Circle 3
B4	10
C4

Formula Trace

=B2*2

Step 1: B2

Step 2: 5 * 2

Cell Reference Map

   A       B       C
1 Circle  Radius  Diameter
2 Circle 1  5  -->  C2
3 Circle 2  7  -->  C3
4 Circle 3 10  -->  C4

The diameter in column C is calculated by referencing the radius in column B for each circle.

Result

   A       B       C
1 Circle  Radius  Diameter
2 Circle 1  5       10
3 Circle 2  7       14
4 Circle 3 10       20

The diameter column now shows values that are twice the radius for each circle.

Sheet Trace Quiz - 3 Questions

What is the diameter of Circle 2 if the radius is 7?

A 7

B 21

C 14

D 10

Key Result

Diameter is calculated as Radius multiplied by 2 (Diameter = Radius * 2).

Practice

1. What does the DIMRADIUS command in AutoCAD measure?

easy

A. The height of a circle

B. The total length around a circle

C. The distance across the circle through its center

D. The distance from the center of a circle to its edge

Solution

1. Step 1: Understand the meaning of radius

   The radius is the distance from the center of a circle to any point on its edge.

2. Step 2: Match the command to the measurement

   DIMRADIUS is used to measure this radius in AutoCAD.

3. Final Answer:

   The distance from the center of a circle to its edge -> Option D

4. Quick Check:

   Radius = center to edge distance [OK]

Hint: Radius = center to edge, use DIMRADIUS [OK]

Common Mistakes:

• Confusing radius with diameter
• Thinking radius measures circumference
• Using DIMDIAMETER instead of DIMRADIUS

2. Which AutoCAD command is used to create a diameter dimension?

easy

A. DIMLINEAR

B. DIMRADIUS

C. DIMDIAMETER

D. DIMANGULAR

Solution

1. Step 1: Identify the command for diameter

   The diameter is the distance across a circle through its center.

2. Step 2: Match the command to diameter measurement

   DIMDIAMETER is the AutoCAD command designed to measure diameters.

3. Final Answer:

   DIMDIAMETER -> Option C

4. Quick Check:

   Diameter uses DIMDIAMETER command [OK]

Hint: Diameter = across circle, use DIMDIAMETER [OK]

Common Mistakes:

• Using DIMRADIUS for diameter
• Choosing linear or angular dimension commands
• Typing command names incorrectly

3. Given a circle with radius 5 units, what will the DIMDIAMETER command display?

medium

A. 5 units

B. 10 units

C. 15 units

D. Cannot determine without center point

Solution

1. Step 1: Understand relationship between radius and diameter

   Diameter is twice the radius, so diameter = 2 x 5 = 10 units.

2. Step 2: Apply DIMDIAMETER command output

   The DIMDIAMETER command will display the diameter value, which is 10 units.

3. Final Answer:

   10 units -> Option B

4. Quick Check:

   Diameter = 2 x radius = 10 units [OK]

Hint: Diameter is double radius, so 5 x 2 = 10 [OK]

Common Mistakes:

• Confusing radius value as diameter
• Forgetting to multiply by 2
• Assuming diameter needs center point input

4. You tried to use DIMDIAMETER on an arc, but the dimension shows an error. What is the likely cause?

medium

A. DIMDIAMETER only works on full circles, not arcs

B. You must select the center point first

C. DIMDIAMETER requires linear objects only

D. The arc is too small to measure

Solution

1. Step 1: Understand DIMDIAMETER limitations

   DIMDIAMETER measures diameter of full circles, not partial arcs.

2. Step 2: Identify why error occurs on arcs

   Since arcs are partial circles, the command cannot calculate full diameter, causing error.

3. Final Answer:

   DIMDIAMETER only works on full circles, not arcs -> Option A

4. Quick Check:

   DIMDIAMETER = full circle only [OK]

Hint: Use DIMRADIUS for arcs, DIMDIAMETER for full circles [OK]

Common Mistakes:

• Trying to select center point manually
• Assuming arcs behave like full circles
• Ignoring command limitations

5. You have a technical drawing with multiple circles and arcs. To clearly show all sizes, which combination of dimension commands should you use?

hard

A. Use DIMRADIUS for arcs and DIMDIAMETER for full circles

B. Use DIMLINEAR for arcs and DIMRADIUS for circles

C. Use only DIMDIAMETER for all circles and arcs

D. Use DIMANGULAR for arcs and DIMDIAMETER for circles

Solution

1. Step 1: Identify dimension types for arcs and circles

   Arcs do not have full diameter, so use DIMRADIUS to measure radius.

2. Step 2: Use DIMDIAMETER for full circles

   Full circles can be dimensioned by diameter using DIMDIAMETER.

3. Step 3: Combine commands for clarity

   Using DIMRADIUS for arcs and DIMDIAMETER for circles ensures clear, accurate dimensions.

4. Final Answer:

   Use DIMRADIUS for arcs and DIMDIAMETER for full circles -> Option A

5. Quick Check:

   Arcs = radius, circles = diameter [OK]

Hint: Arcs need radius, circles can use diameter [OK]

Common Mistakes:

• Using DIMDIAMETER on arcs causing errors
• Mixing linear or angular dimensions incorrectly
• Not differentiating arcs from full circles