KINEMATICS

vector	displacement	velocity	acceleration
scalar	dist	speed	acceleration

Av. Speed = dist/time (av. vel = displacement/time) > s = vt
Acc, = change in vel/time = (final-initial)vel./ time = (v-u)/t > a = (v-u)/t > v = u + at
linear motion- motion along a straight line

Distance-time, speed-time, acceleration-time graphs

Description:
-curve / straight line
-gradient: increase, decrease / constant
-s/v/a: increase, decrease / constant (increase/decrease-uniformly?)
-s/v/a: from (x > y)units

v = u + at ..(1)
s = (u+v)t/2 ..(2)
s = ut + ½at² ..(3)
v² = u² + 2as ..(4)
sub (1) in (2) > s = ut + ½at² ..(3)
from (1): t = (v-u)/a (i), sub (i) in (2) > v² = u² + 2as ..(4)

Projectile motion- obj projected into air w/ initial speed u at angle, θ° wrt ground [a_x = 0, |a_y| = g, a_y = -g]


Free fall: F_gravity exerts pull on obj at any pt on its surface, body falls freely, F_gravity gives uniform acc (9.81m/s²), air resistance + upthrust ignored
Air resistance: speed ^, R_air ^, obj in free fall: R_air ^ > R_air = weight of obj > no net force > acc = 0 > constant speed (vel) = terminal vel


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