  In recent years there has been growing evidence that even after teaching
designed to address the learning difficulties dictated by literature, many
physics learners fail to create the proper reasoning chains that connect the
fundamental principles and lead to reasoned predictions. Even though students
have the required knowledge and skills, they are often based on a variety of
intuitive reasoning that leads them to wrong conclusions. This research studies
students' reasoning on science problems through heuristic - analytical thought
processes (System 1 - System 2). System 1 operates automatically and quickly
with little or no effort and no sense of voluntary control, while System 2
focuses on the demanding mental activities that require it and is slow based on
rules. Specifically, we seek to study those cognitive processes and information
available to students when they face science problems and, therefore, to
explore the various heuristic processes that students use when solving physics
problems. Our results indicated four intuitive heuristics in students' minds
when they solve problems in Mechanics and especially in the unit projectile
motion: associative activation, processing fluency, attribute substitution and
anchoring effect. These heuristics prevent students from applying knowledge and
methods that they already possess to solve a physics problem.
