Young's modulus is a crucial mechanical property in engineering, as it defines the stiffness of a material and tells us how much it will deform for an applied stress. In this video I take a detailed look at Young's modulus, starting with tensile tests and stress-strain curves, all the way through to what is happening at the atomic scale. --- ERRATA: - At 05:27 steel is incorrectly shown as being a substitutional alloy. It is actually an interstitial alloy, where the carbon atoms are located between the iron atoms. --- If you would like to support the channel, please consider becoming a Patron - This will allow me to create more high quality videos covering a range of engineering topics. --- The Efficient Engineer is a channel aimed at mechanical and civil engineers. The mission is to simplify engineering concepts, one video at a time! Follow me on Twitter: