Ch.1 Physics study guide

Newton’s law describe…

how forces relate to changes in motion and how

interacting objects push or pull on each other

inertia

resistance to changing motion

mass measures…

inertia

• larger mass is harder to accelerate

force (N -newton - 1 kg/m/s²)

is a push or pull

constant velocity means…

both constant speed and constant direction

If velocity is constant…

acceleration is 0 and the net force is 0

final velocity with constant acceleration

Vf = Vi + a /\t

velocity-position relation

Vf² = Vi² + 2a/\x

position with constant acceleration

Xf = Xi + Vi/\t + (1/2)a(/\t)²

If an object starts from rest…

Vi = 0

Aristotle

• thought motion needed a continuing cause

Galileo

• no force is needed to keep constant straight-line motion going

Cartesian

• coordinates matter because physics uses positive and negative directions to represent motion and forces

slope on graph

represents a rate of change

position-time slope is…

velocity

velocity-time slope is…

acceleration

displacement from a velocity-time graph comes from…

a signed area not slope

mass

kilogram (kg)

velocity or speed

m/s

• velocity → direction

• speed → how fast

acceleration

m/s²

• means velocity changes each second

time

seconds (s)

position or displacement

meters (m)