A1 - Kinematics

displacement

• change in position

• is a vector quantity

• s_final - s_initial

distance travelled

the actual length of the path followed

average speed

total distance travelled divided by time taken

uniform motion

in equal intervals of time, the position changes by the same amount (constant velocity)

velocity in uniform motion

displacement divided by time

average speed

total distance travelled divided by the time taken

instantaneous speed

magnitude of the velocity

acceleration

rate of change of velocity

when can equations of kinematics (SUVATs) be used?

when acceleration is constant

what is horizontal acceleration in projectile motion?

0, velocity is constant because gravitational force only acts downwards

what is vertical acceleration in projectile motion>

9.8m/s, since gravity acts downwards. This can change if on a different planet or smth ygm

fluid resistance force relative to velocity

proportional to v at low speeds, and v² at high speeds

terminal speed

the speed reached when resisting forces are equal to gravitational force, so there is no vertical acceleration and speed is constant