From 0227a26143f386279dd03fd12356fa0fafb33686 Mon Sep 17 00:00:00 2001 From: eggy Date: Thu, 15 Oct 2020 15:01:54 -0400 Subject: [PATCH] phys: add some simple projectile motion derivable formulas --- docs/sph3u7.md | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/docs/sph3u7.md b/docs/sph3u7.md index 7ac1af8..ef9c455 100644 --- a/docs/sph3u7.md +++ b/docs/sph3u7.md @@ -316,7 +316,9 @@ By the formula of the gradient and the formula for the area underneath an accele **Projectile motion** is uniformly accelerated motion that does not leave the vertical plane (is two-dimensional). Note that the two directions (horizontal and vertical) that the projectile moves in are independent of one another. This means that variables such as average velocity can be calculated by breaking up the motion into vector **components**, then finding the resultant vector. -Projectiles move at a constant horizontal velocity and move at a uniformly accelerated velocity (usually $9.81 \text{ ms}^2 \text{ [down]}$). +Projectiles move at a **constant** horizontal velocity and move at a uniformly accelerated velocity (usually $9.81 \text{ ms}^2 \text{ [down]}$). + +Therefore the horizontal velocity of a projectile ($v_x$) is constant and is equal to $v \cos \theta$ and the vertical velocity ($v_y$) is equal to $v \sin \theta$ where $\theta$ is the direction of $\vec{v}$ above the horizontal axis. ## 2.2 - Forces