Accessory – Physics Experiences - Photo Frame Catapult Ball Physics is a word that has its origin in ancient Greek, "physis", which means "nature." It is the science that
studies the properties of matter and natural forces through observation and experimentation, establishing logical schemes for each. Physics is considered a fundamental science, based on theories and seeking to establish itself in experiments (www.significadosbr.com.br).
Currently, it is very difficult to define the physics playing field, as it appears in different fields of knowledge that, at first sight, seem completely unrelated. Their formulations are generally expressed in mathematical language.
The Spring is a metal piece, with elasticised, spiral or helical and reacts when bent, stretched or
compressed. It is a marvel of human engineering and creativity. That comes in so many varieties – the compression spring, the extension spring, the torsion spring, the coil spring, etc. – all of which serve different
and specific functions. These functions in turn allow for the creation of many man-made objects. (www.universetoday.com)
Hooke’s Law is a principle of physics that a spring has a spring constant k. This constant is obeyed to
a certain limit where the spring deformation in question becomes permanent. Within the limit where Hooke's
law is valid, the spring can be compressed or elongated, returning to the same equilibrium position. This can be expressed mathematically as F= -kX, where F is the force applied to the spring (either in the form
of strain or stress); X is the displacement of the spring, with a negative value demonstrating that the displacement of the spring once it is stretched; and k is the spring constant and details just how stiff it is. The law is named after 17th century British physicist Robert Hooke, who sought to demonstrate the relationship between the forces applied to a spring and its elasticity. (www.universetoday.com)
Isaac Newton was an English scientist, recognized as physicist and mathematician. His work, Philosophiae
Naturalis Principia Mathematica, is considered one of the most influential in the history of science. Published in 1687, this work describes the law of universal gravitation and the three laws of Newton, who based the classical mechanics (http://whowasisaacnewton.com). The laws of mechanics are:
• 1st law - Principle of Inertia - says a stationary object and a moving object tend to remain as they are unless an external force acts on them.
• 2nd Law - Fundamental Principle of Dynamics - The resultant force acting on a body is proportional to the
product of the mass by the acceleration acquired by it. Equation: F = m. a (F - Force; m - mass; a – acceleration).
• 3rd law - Principle of Action and Reaction - says that for every action there is an equal and opposite reaction.
Catapults are circus mechanisms using a sort of arm to throw an object (stones, ball, etc.) at a great distance, thus avoiding possible obstacles such as walls and moats or target. Catapults can be classified according to the physical concept used to store and release energy required to throw (http://whowasisaacnewton.com).
Accessory Create: Photo Frame Catapult Ball Hooke´s law: The deforming forces are proportional to the elastic deformation produced. But this happens because of the second Newton's law: F = m.a. The force applied in the spring is proportional to the deformation (Hooke´s Law). This proportionality is due to the second Newton's law: force = mass x applied acceleration.
In case of the object, the Hooke´s law occurs only when the object is stationary. And in this case, the acceleration (a) is the force of gravity (g). Then, F = m.g. The third law of Newton also applies: for every action
there is a reaction. From same intensity and opposite directions. The force applied in the spring is the law of
gravity, which is proportional to the force of spring up. So when you balance the spring, it tends to go back to the place.