Vectores

I. Introduction

The experiment 4: Projectile, studied the concept of the projectile’s motion and the factors that are involved in this movement. A projectile is any object that once projected or dropped continues in motion by its own inertia and is influenced only by the downward force of gravity (9.8m/s2). There are a variety of examples of projectiles (when the air resistance is negligible)as: an object dropped from rest, an object that is thrown vertically upward and an object which is thrown upward at an angle to the horizontal. There are the two components of the projectile's motion - horizontal and vertical motion. These two components of motion are perpendicular to each other and must be discussed separately. Gravity, as the downward force upon a projectile influences itsvertical motion and causes the parabolic trajectory that is characteristic of projectiles. The horizontal motion of the projectile is the result of the tendency of any object in motion to remain in motion at constant velocity (acceleration is 0). When the projectile is launched horizontally, the projectile travels at that direction with a constant horizontal velocity and zero acceleration, and then itwill fall in a vertical direction with a uniformly varied motion due to the acceleration of gravity. The horizontal range is the displacement in horizontal direction. There is no acceleration involved in this direction. Motion is a uniform motion. It follows that horizontal range is transverse with the horizontal component of the projection velocity for the time of flight (T). In the case that theprojectile is launched with a different angle, the projectile would travel with a parabolic trajectory. The downward force of gravity would act upon the object to cause the vertical downward acceleration as free fall. The force of gravity acts downward and is unable to alter the horizontal motion because the components of motion are independent of each other. One can calculate the horizontaldirection at a determinant time with: initial velocity (m/s) per time(s), {X= VX0 (T)}. In the vertical motion, one can calculate the height and time with the formula: y= y 0 + VY0 + 1/2 gt2 (in which y 0 =0) and also it can be calculate VY at a determinant time with the formula: V= gt2. To calculate the component of motion, one could use the formulas: for X components VX= VCOS θ and for Ycomponents Vy= VSIN. The general properties of projectile movement were studied in the experiment by comparing observed and calculated values. And by recording the characteristics of motion such as the launch angle, initial speed, range and flight time.

II. Procedure and materials

In the experiment of projectile, the equipment consists of: a projectile launcher, 2 Photo gate, a ball, a platformfor determining flight time, a ruler, a jack and a carbon and white paper. The projectile launcher used in the experiment have 3 different reproducible release rates, launch angle continuously adjustable, constant release height and the ejection of the ball almost with no rotation to perform the most accurate projectile launch. In the projectile was attached to the side, 2 photo gate connected tochannel 1 and 2 of interface to sensor the initial velocity and trajectory of the projectile. The ball landed in the platform for flight time connected to channel 3, that determinate the time of the trajectory when the ball is in the air. In the first part of the experiment was executed a horizontal launch at an angle of 0 °. When the angle was set, the ball was putted in the barrel of thelauncher and pressed tight in the short-range position. Then, the experiment progressed running a test launch until the ball fell correctly in the platform. Later was placed a white and carbon paper over the platform to mark where the ball fell. Next, the ball was recharged in the pitcher, at the short-range position and when the time began to ran, the ball shoots. The initial velocity, the...