# Search results

1. ### Ultimate Tensile strength of ductile materials

In case of ductile materials we know that there is a substantial difference between the ultimate tensile strength and yield strength. As long as the specimen stress is below the yield strength we need not worry about engineering stress and true stress, as they as essentially same. But when...
2. ### Doubt on Fatigue Strength S-N diagrams

A standard way of plotting an S-N (fatigue strength vs no of cycles) graph is to start off by taking a value of Sm (for N=1000) cycles and joining it to the point depicting Se(Endurance Limit). Now we commonly take Sm= 0.9Sut for steels. Now I was wandering, before you actually get to use the...
3. ### Doubt Regarding Shearing Stresses In a Beam

Thank you AlephZero for the reply, but could you please elaborate which integral you are talking about. The derivation for shear stress the way I know it is that you take forces due to moments (axial) for a small element in either direction. If the element length is dx the change in moment is dM...
4. ### Doubt Regarding Shearing Stresses In a Beam

Thank you pukb for your reply. SO basically its right when i say that the shear stresses in the xy(towards the downward portion) is actually zero. Which means maybe the material out there does not tend to get sheared? Maybe true but hard to digest. I am having problems as to how to visualize...
5. ### Doubt Regarding Shearing Stresses In a Beam

Lets say we have a beam which is simply supported at the two extreme ends(support conditions dont matter in my question). A concentrated transverse load is applied at the halfway point. Now lets say we take a section at x= L/3 where is L the length of the beam. Now we know that transverse shear...
6. ### Roll cage design

I would like to thank you both for your replies... But before I go ahead I would like to correct myself... Max speed is 60 mph and not 6. So coming to what I did. I think I should go ahead by building a Base first. We are planning on going for something with a rectangular outline with a front U...
7. ### Roll cage design

As of now my only concrete source were SAE Baja Team reports. But My situation is different. Out there they had fixed the thickness and outer diameter of the roll cage tubes and the basic structure of the roll cage was fixed - All part of the rules. In my case i dont know how to start. All I...
8. ### Roll cage design

I am a bachelors mechanical engineering student with a decent factual knowledge about cars and how they work. But i am a novice with no experience when it comes to design. Now I (along with 3 other guys) have been assigned the task of designing the roll cage of an electric car. I did not get any...