From e36996ee13ef12091a2f7abf3bfd7503aeee3fec Mon Sep 17 00:00:00 2001 From: eggy Date: Tue, 20 Oct 2020 18:34:04 -0400 Subject: [PATCH] phys: switch to concise vector labelling, fix formatting errors --- docs/sph3u7.md | 12 ++++++------ 1 file changed, 6 insertions(+), 6 deletions(-) diff --git a/docs/sph3u7.md b/docs/sph3u7.md index 842f162..c5726f8 100644 --- a/docs/sph3u7.md +++ b/docs/sph3u7.md @@ -324,7 +324,7 @@ Therefore the horizontal velocity of a projectile ($v_x$) is constant and is equ A force is a "push" or "pull" exerted by one object acting on another object and is always represented in the form of a vector. The SI unit for force is the newton ($\text{N}$), equivalent to $\text{kg} \cdot \text{m} \cdot \text{s}^{-2}$. -Forces do not cause motion but instead cause *changes* in motion; therefore a constant force on an object results in uniformly acceleration motion**. +Forces do not cause motion but instead cause *changes* in motion; therefore a constant force on an object results in **uniformly accelerated motion**. A force must have: @@ -352,7 +352,7 @@ Contact (the two objects are touching) forces: Non-contact forces: - - **Weight** ($\vec{W}$) is the attraction between a mass and a planet. Its vector always points toward the planet. The magnitude of weight is equal to the mass of the object times the acceleration due to gravity ($mg#). + - **Weight** ($\vec{W}$) is the attraction between a mass and a planet. Its vector always points toward the planet. The magnitude of weight is equal to the mass of the object times the acceleration due to gravity ($mg$). - **Electromagnetic forces** ($\vec{F_M}$ and $\vec{F_E}$) are not covered in this course. The origin and target of a force are placed in the subscript of that force. @@ -360,10 +360,10 @@ The origin and target of a force are placed in the subscript of that force. !!! example If a rock is pushed across the ground by a hand at a constant velocity, the forces acting on the rock would include: - - the normal force from the hand, or $F_{T \text{ h-R}}$ - - the kinetic friction from the ground, or $F_{fK \text{ g-R}}$ - - the weight of the rock from the planet, or $W_\text{ E-R}$ - - the normal force from the ground pushing against the rock's weight, or $F_{N \text{ g-R}}$ + - the normal force from the hand, or $F_{T \text{ hR}}$ + - the kinetic friction from the ground, or $F_{fK \text{ gR}}$ + - the weight of the rock from the planet, or $W_\text{ ER}$ + - the normal force from the ground pushing against the rock's weight, or $F_{N \text{ gR}}$ ### Force diagrams