### Introduction

This Section returns to the simple models of projectiles considered in Section 34.1. It explores the magnitude of air resistance effects and the effects of including simple models of air resistance on the earlier analysis.

#### Prerequisites

- be able to solve second order, constant coefficient ODEs
- be able to use Newtonâ€™s laws to describe and model the motion of particles

#### Learning Outcomes

- compute the effect of air resistance proportional to velocity on particles moving under gravity
- define terminal velocity for linear and quadratic dependence of resistance on velocity

#### Contents

1 Resisted motion1.1 Resistance proportional to velocity

1.2 Quadratic resistance

1.3 Vertical motion with quadratic resistance