Factor of safety analysis in Solidworks - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to calculate the factor of safety by dividing the material strength by the applied stress.

Solidworks

FactorOfSafety = MaterialStrength [1] AppliedStress

Drag options to blanks, or click blank then click option'

A/

B*

C+

D-

Attempts:

3 left

💡 Hint

Common Mistakes

Using multiplication instead of division

Adding or subtracting values incorrectly

The factor of safety is calculated by dividing the material strength by the applied stress to ensure the design is safe.

2fill in blank

medium

Complete the code to check if the factor of safety is greater than the required safety factor.

Solidworks

IsSafe = FactorOfSafety [1] RequiredSafetyFactor

Drag options to blanks, or click blank then click option'

A<

B==

C>

D<=

Attempts:

3 left

💡 Hint

Common Mistakes

Using less than instead of greater than

Using equality instead of comparison

The design is safe if the factor of safety is greater than the required safety factor.

3fill in blank

hard

Fix the error in the code to correctly calculate the factor of safety using the minimum yield strength and maximum stress.

Solidworks

FactorOfSafety = [1] / [2]

Drag options to blanks, or click blank then click option'

AMaxStress

BAverageStress

CMinYieldStrength

DMaxYieldStrength

Attempts:

3 left

💡 Hint

Common Mistakes

Using max stress as numerator

Using average stress instead of max stress

The factor of safety is the ratio of minimum yield strength to maximum stress.

4fill in blank

hard

Fill in the blanks to calculate the factor of safety and check if it meets the design criteria.

Solidworks

FactorOfSafety = [1] / [2]
IsDesignSafe = FactorOfSafety [3] RequiredSafetyFactor

Drag options to blanks, or click blank then click option'

AMinYieldStrength

BMaxStress

C>

D<

Attempts:

3 left

💡 Hint

Common Mistakes

Using wrong variables for calculation

Using less than instead of greater than for safety check

The factor of safety is minimum yield strength divided by maximum stress. Then check if it is greater than the required safety factor.

5fill in blank

hard

Fill all three blanks to calculate the factor of safety, compare it to the required safety factor, and output the safety status.

Solidworks

FactorOfSafety = [1] / [2]
IsSafe = FactorOfSafety [3] RequiredSafetyFactor
SafetyStatus = "Safe" if IsSafe else "Unsafe"

Drag options to blanks, or click blank then click option'

AMinYieldStrength

BMaxStress

C>

D<

Attempts:

3 left

💡 Hint

Common Mistakes

Using wrong comparison operator

Mixing up variables in calculation

Calculate factor of safety by dividing minimum yield strength by maximum stress. Then check if it is greater than required safety factor to determine safety status.

Practice

1. What does the factor of safety (FoS) represent in SolidWorks analysis?

easy

A. The speed at which the simulation runs

B. The total weight of the model

C. The ratio of material strength to the maximum expected stress

D. The number of parts in the assembly

Solution

1. Step 1: Understand the definition of factor of safety

   The factor of safety is a measure comparing how strong a material is versus the stress it will face.

2. Step 2: Relate factor of safety to design safety

   A higher factor of safety means the design is safer because the material can handle more stress than expected.

3. Final Answer:

   The ratio of material strength to the maximum expected stress -> Option C

4. Quick Check:

   FoS = Strength / Stress [OK]

Hint: Remember FoS = strength divided by stress [OK]

Common Mistakes:

• Confusing FoS with weight or speed
• Thinking FoS is the number of parts
• Ignoring the stress in calculation

2. Which of the following is the correct way to interpret a factor of safety value of 1.5 in SolidWorks simulation?

easy

A. The model has 1.5 parts

B. The material can withstand 1.5 times the expected stress

C. The simulation ran 1.5 times faster

D. The material will fail at 1.5 units of stress

Solution

1. Step 1: Understand what a factor of safety value means

   A factor of safety of 1.5 means the material strength is 1.5 times greater than the stress it will experience.

2. Step 2: Interpret the value in context

   This means the design is safe up to 1.5 times the expected load before failure.

3. Final Answer:

   The material can withstand 1.5 times the expected stress -> Option B

4. Quick Check:

   FoS = 1.5 means 1.5x strength [OK]

Hint: FoS > 1 means material stronger than stress [OK]

Common Mistakes:

• Thinking FoS is a stress value
• Confusing speed or parts with FoS
• Assuming FoS less than 1 is safe

3. Given a material strength of 300 MPa and a maximum stress from simulation of 150 MPa, what is the factor of safety?

medium

A. 2

B. 0.5

C. 450

D. 150

Solution

1. Step 1: Identify the formula for factor of safety

   Factor of safety = Material strength / Maximum stress.

2. Step 2: Calculate using given values

   FoS = 300 MPa / 150 MPa = 2.

3. Final Answer:

   2 -> Option A

4. Quick Check:

   300 / 150 = 2 [OK]

Hint: Divide strength by stress to get FoS [OK]

Common Mistakes:

• Multiplying instead of dividing
• Using stress divided by strength
• Confusing units or values

4. A SolidWorks simulation shows a factor of safety less than 1 for a part. What is the most likely cause?

medium

A. Material strength is less than the applied stress

B. Simulation ran too quickly

C. The part has too many features

D. The model is missing a material assignment

Solution

1. Step 1: Understand what FoS less than 1 means

   A factor of safety less than 1 means the stress exceeds the material strength, indicating failure risk.

2. Step 2: Identify the cause from options

   Material strength being less than applied stress directly causes FoS < 1.

3. Final Answer:

   Material strength is less than the applied stress -> Option A

4. Quick Check:

   FoS < 1 means stress > strength [OK]

Hint: FoS < 1 means unsafe: stress > strength [OK]

Common Mistakes:

• Blaming simulation speed
• Thinking number of features affects FoS
• Ignoring material assignment impact

5. You have a part with a factor of safety of 0.8 under current load. To improve safety, you can either increase material strength or reduce load. If increasing strength by 25% is not possible, by what percentage must you reduce the load to achieve a factor of safety of 1.2?

hard

A. 40%

B. 50%

C. 20%

D. 33.3%

Solution

1. Step 1: Understand the relationship between FoS, strength, and load

   FoS = Strength / Load. Strength is fixed, so reducing load increases FoS.

2. Step 2: Calculate required load reduction

   Current FoS = 0.8 = Strength / Load. So Load = Strength / 0.8.
   Desired FoS = 1.2 = Strength / New Load.
   New Load = Strength / 1.2.
   Percentage reduction = ((Old Load - New Load) / Old Load) * 100 = ((Strength/0.8 - Strength/1.2) / (Strength/0.8)) * 100 = ((1/0.8 - 1/1.2) / (1/0.8)) * 100 = ((1.25 - 0.8333) / 1.25) * 100 = (0.4167 / 1.25) * 100 = 33.33%.

3. Final Answer:

   33.3% -> Option D

4. Quick Check:

   Reduce load by 33.3% to raise FoS to 1.2 [OK]

Hint: Use FoS = strength/load and solve for load reduction [OK]

Common Mistakes:

• Trying to increase strength when not allowed
• Calculating percentage incorrectly
• Mixing up load and strength in formula