That, of course, made us start thinking about how our different designs might affect the trajectory. We decided to create a Magna-Tile tower, and see which square the projectile hit as a way of measuring the height. We started with a six square high Magna-Tile tower, and our projectiles shot straight over the top! So we had to modify our experiment by adding extra height to our tower, and adjusting the position of the starting line.
It took us a few tries before we found a test that worked for all three catapults. In the end, we discovered we needed a very high tower indeed! Catapults have been used for thousands of years, and come in all shapes and sizes. They can be as simple as a slingshot, or as complicated as a large trebuchet used to launch huge boulders to knock down a castle wall. The trajectory is the path that the projectile takes as it flies through the air.
So, I guess you might be wondering which catapult launched the furthest projectile? Which one had the highest trajectory? Which one had the most consistent results? Sorry, that would be spoiling the fun. For more physics fun, you might also like to check out the ideas on our Fun Physics Activities page, including:. And, of course, you can always subscribe to our newsletter , to receive all our latest activities via email. An affiliate link means I may earn a referral fee or commission if you make a purchase through my link, without any extra cost to you.
Some old ones are kept in museum s. Castles and fortified walled cities were common during this period — and catapults were used as a key siege weapon against them. As well as attempting to breach the walls, incendiary missiles could be thrown inside—or early biological warfare attempted with diseased carcasses or putrid garbage catapulted over the walls. Defensive techniques in the Middle Ages progressed to a point that rendered catapults ineffective for the most part.
The Viking siege of Paris —6 A. The last large scale military use of catapults was during the trench warfare of World War I. During the early stages of the war, catapults were used to throw hand grenades across no man's land into enemy trenches. They were eventually replaced by small mortars. In the s the invention of vulcanized rubber allowed the making of small hand-held catapults, either improvised from Y-shaped sticks or manufactured for sale; both were popular with children and teenagers.
These devices were also known as slingshots in the USA. It makes use of torsion tension around an axis "stored" in ropes, but these drive a "flinging" arm when cut rather than hurl contents such as rocks or even fire in a "piston-like" motion. While having a greater range than the ballista, the mangonel was notoriously inaccurate. It was, however, lighter and easier to move from place to place. The basic design of a trebuchet is a lever, with a short arm facing the enemy and a longer arm being the business portion; an axle separates the two.
A counterweight is applied to the shorter arm to add force at the point the projectile is released from a sling. This catapult comes in two forms. The first, a traction trebuchet , was operated by a group of soldiers pushing down on the short arm before release. The other, a counterpoise trebuchet , worked by having the soldiers focus their efforts mainly on pulling down the long arm instead before release.
The science behind catapults is easily explained using the equations of projectile motion. The key thing to remember about any projectile-motion problem is that once the projectile has been released, the only force it is subjected to is that of its own weight resulting from gravity.
When a projectile is released, it has both horizontal and vertical components of motion. Luckily for physicists and students, these can be analyzed separately, since gravity does not affect horizontal motion. Thus if you want to launch a projectile as far as possible, point it exactly halfway to a point directly overhead and fire away! Kevin Beck holds a bachelor's degree in physics with minors in math and chemistry from the University of Vermont.
Formerly with ScienceBlogs.
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