Vernier Software & Technology

# Frictional Forces

## Introduction

Friction is a force that resists motion. It involves objects in contact with each other, and it can be either useful or harmful. Friction helps when you want to slow or stop a bicycle, but it is harmful when it causes wear on the parts of a machine. In this activity, you will study the effects of surface smoothness and the nature of materials in contact on sliding friction. You will use a Force Sensor to measure frictional force, in Newtons (N), as you pull a block across different surfaces.

## Objectives

In this experiment, you will

• Measure sliding friction.
• Measure friction between a wooden block and smooth-surface wood.
• Measure friction between a wooden block and rough-surface wood.
• Make predictions about other surfaces.

## Sensors and Equipment

This experiment features the following Vernier sensors and equipment.

### Option 3

You may also need an interface and software for data collection. What do I need for data collection?

## Middle School Science with Vernier

See other experiments from the lab book.

 1 A Hot Hand 2 Heating of Land and Water 3 The Greenhouse Effect 4 Relative Humidity 5 Soil Study 6 Absorption of Radiant Energy 7 Reflectivity of Light 8 Schoolyard Study 9 A Good Sock 10 What Causes the Seasons? 11 Solar Homes 12 Ocean Floor Mapping 13 Boiling Temperature of Water 14 Freezing and Melting of Water 15 How Low Can You Go? 15B Ziplock Ice Cream 16 A Good Cold Pack 17 Lemon "Juice" 18 Get a Grip! 19 Fun with Pressure 20 Water Hardness Study 21 Diffusion: How Fast? 22 A Water Field Study 23 Cooling Rates: Shaq vs. Susie 24 Yeast Beasts in Action 25 Heart Rate and Body Position 26 Heart Rate and Exercise 27 Mapping a Magnetic Field 28 Electromagnets 29 Frictional Forces 30 First-Class Levers 31 Pulleys 32 Buoyancy 33 Graphing Your Motion 34 Speeding Up 35 The Indy 100 35B Pencil Car 36 Crash Dummies 37 Falling Objects 38 A Speedy Slide

### Experiment 29 from Middle School Science with Vernier Lab Book

#### Included in the Lab Book

Vernier lab books include word-processing files of the student instructions, essential teacher information, suggested answers, sample data and graphs, and more.