In contrast, motion in the horizontal axis does not require these equations because horizontal acceleration is zero.

Motion in the vertical axis can be modelled using rectilinear equations.

Initial horizontal velocity remains constant and does not change.

Its magnitude decreases when a object travels upwards and increases when it travels downwards. Initial vertical velocity changes throughout projectile motion.Find its initial horizontal and vertical velocities.Ĭonstruct a right-angled triangle from vectors: Situations in which this type of initial velocity occurs will be explored and clarified in practice questions later.Ī projectile is launched at 60 ms -1 at an elevation of 30 0. The initial velocity can be negative because the initial direction of a projectile can also be downwards as shown below. Since the triangle is right-angled, the three vectors’ relationship can also be summarised by Pythagoras’s theorem.The relationship between initial vertical and horizontal velocity is described by:.Using trigonometry, initial horizontal and initial vertical velocities can be expressed in terms of the initial velocity. Practice applying formulas to calculate horizontal and vertical projectile motion with the cannon ball and Eiffel Tower practice problems. The relationship between initial velocity, initial horizontal and vertical velocity can always be represented by the right-angled triangle with q (as shown in the diagram) is the angle at which the projectile leaves the horizontal plane (usually the ground). The motion of a projectile object is impacted by gravity.Initial horizontal velocity is typically written as u x– subscript x is used to represent the horizontal rectilinear motion.

Initial vertical velocity is typically written as u y– subscript y is used to represent the vertical rectilinear motion.Initial velocity is typically written as u.This is done by constructing a right-angled triangle from vectors. The initial velocity can always analysed as and resolved into two components: horizontal and vertical velocities.All objects at the beginning of their projectile motion must possess a non-zero initial velocity.Solve problems, create models and make quantitative predictions by applying the equations of motion relationships for uniformly accelerated and constant rectilinear motion.Apply the modelling of projectile motion to quantitatively derive the relationships between the following variables:.

Projectile motion equation