A SciShow Kids viewer wrote us to ask how bridges are strong enough to carry cars and trucks! Jessi and Squeaks can explain -- with blocks! ---------- Like SciShow? Want to help support us, and also get things to put on your walls, cover your torso and hold your liquids? Check out our awesome products over at DFTBA Records: http://dftba.com/SciShow Or help support us by becoming our patron on Patreon: https://www.patreon.com/scishow ---------- Looking for SciShow elsewhere on the internet? Facebook: http://www.facebook.com/scishow Twitter: http://www.twitter.com/scishow Tumblr: http://scishow.tumblr.com Instagram: http://instagram.com/thescishow SOURCES: http://www.k5architecture.org/pdf/g2%20-%20Grade%202.pdf http://www.pbs.org/wgbh/buildingbig/lab/shapes.html http://www.childrensengineering.com/ http://www.design-technology.org/suspensionbridges.htm http://wyrk.com/busiest-bridge-in-world-dales-daily-data/)