Mechanical properties of solid

Thread starter starablaze
Start date Oct 8, 2008
Tags

Mechanical Mechanical properties Properties Solid

AI Thread Summary

Pillars, columns, and railway lines are designed in an 'I-shape' to optimize strength and stiffness while minimizing material use. The top and bottom flanges of the beam carry most of the load, effectively distributing weight and preventing buckling. The moment of inertia plays a crucial role in determining stiffness, allowing for a balance between structural integrity and material efficiency. Proper application of these principles can lead to significant savings in both weight and cost. Understanding these mechanical properties is essential for effective engineering design.

Oct 8, 2008

starablaze

why are pillars and columns and railway lines 'I-shaped'? how is buckling prevented? howis the weight distributed?

Physics news on Phys.org

Oct 8, 2008

granpa

most of the strength of a beam comes from the top and bottom parts.

Oct 8, 2008

russ_watters

Mentor

Insights Author

Stiffness is a function of moment of inertia: http://en.wikipedia.org/wiki/Moment_of_inertia

Using the concept properly enables saving on materials (saving weight and money) while maximizing strength.

Thread '1:1 versus 2:1 Mechanical Advantage debate'

The rope is tied into the person (the load of 200 pounds) and the rope goes up from the person to a fixed pulley and back down to his hands. He hauls the rope to suspend himself in the air. What is the mechanical advantage of the system? The person will indeed only have to lift half of his body weight (roughly 100 pounds) because he now lessened the load by that same amount. This APPEARS to be a 2:1 because he can hold himself with half the force, but my question is: is that mechanical...

View full post »

Thread 'Average velocity as a weighted mean'

Hello everyone, Consider the problem in which a car is told to travel at 30 km/h for L kilometers and then at 60 km/h for another L kilometers. Next, you are asked to determine the average speed. My question is: although we know that the average speed in this case is the harmonic mean of the two speeds, is it also possible to state that the average speed over this 2L-kilometer stretch can be obtained as a weighted average of the two speeds? Best regards, DaTario

View full post »

Thread 'Newton's first law?'

Some physics textbook writer told me that Newton's first law applies only on bodies that feel no interactions at all. He said that if a body is on rest or moves in constant velocity, there is no external force acting on it. But I have heard another form of the law that says the net force acting on a body must be zero. This means there is interactions involved after all. So which one is correct?

View full post »