# The Moving Man

The applet The Moving Man enables students to experiment and learn about motion, position, velocity and acceleration. The movements of the man are plotted in charts.

• Move the little man back and forth with the mouse and plot his motion.
• Set the position, velocity, and/or acceleration and let the simulation move the man for you.

#### Learning Goals

• Interpret, predict charts/graphs on position, velocity and acceleration.
• Describe, make sense of and reason about the charts.

If you register at the PHET website as a teacher, you have access to the information for teachers. The website offers examples of worksheets and questions for students at different levels.

Students can make a graph that fits a story, or make a story that fits a chart. At primary school level focus on one chart in the beginning. For example: What is the story behind this chart?

Do not underestimate the complexity of only the first chart. It shows a timeline, the position, negative numbers, and a man who covers a distance.

 Purchase Free Hardware PC Requirements browser, JAVA

# Density and Buoyancy

Density and Buoyancy is a simulation from the GoLabz project. The game uses colored cubes that can be dropped into an aquarium. Students can experiment with different volume, mass or density.

The program is one of many simulations by PHET, designed and developed by the University of Colorado.

You can download a worksheet Density and Buoyancy for this game.

In addition to the game it would be great to use real cubes of different materials in an aquarium with real water. The students can make their own mystery cubes, of which the appearance does not give away the type of material used. Cubes should also be made water proof.

 Purchase Free Hardware PC, iPad Requirements browser

# Design Bridges

The Bridge Designer program is part of the Bridge Design Contest for civil engineers. The program enables students to design bridges, test the design, and analyse the test results. Both construction and costs are important factors. The design is part of a contest among students, but can also be used without participation in the contest. After the design a simulation of a truck crossing the designed bridge can be viewed.

The software Bridge Designer (2015) can be downloaded for free and is different for every new yearly contest.

The design requires a set of choices that influence the overall construction, the architecture, the costs. Thereafter the details have to be designed choosing from multiple options in terms of number of joints and supports, type of material etc.

Apart from use at university level among (civil)engineering students, the program could also be used as a tool to prepare a design of a bridge at secondary school level. Hereby, the tool could be used as an intrioduction. The program visualises the different type of constructions used in building bridges and their names.

Despite the high level of data and complexity of the designs you can make, is Bridge Designer  a highly interactive and intuitive program.

 Purchase Free Hardware PC, Mac Requirements Java

# Balancing Act

Balancing Act is a simulation from the GoLabz project. The game uses a simulation with a balance scale. Students have to solve problems which involve the relation between weight and position of the weight on the balance scale.

The Balancing Act program is one of many simulations by PHET, designed and developed by the University of Colorado.

Are students able to find the rule by which all problems can easily be solved?

 Purchase Free Hardware PC, iPad Requirements browser

# Energy Skate Park

Energy Skate Park is a simulation from the GoLabz project. The simulation introduces the basics of energy conservation.

The program is one of many simulations by PHET, designed and developed by the University of Colorado.

We have given students age 10-12 some tasks while using this simulation. See below.

 Purchase Free Hardware PC, iPad Requirements browser

Find out about a skate boarder and design a skate park on Energy Skate Park simulation.

Issues to investigate:

Intro

1. What is mass?
2. Does the weight of the skater influence his/her speed?If yes, how?
3. How does the size and weight of the skater influence the total energy?
4. What does the bar graph tell you about energy?
5. Use the bar graph to find out what is meant by kinetic energy and potential energy?
6. The skater continues endlessly? How is this possible? Is this realistic? Why/why not?

Friction

1. What does friction do?
2. What kind of energy is related to friction?
3. Does friction have (1) a larger,  (2) a smaller,  or (3) the same impact on a big skater than on a small skater?
4. Match the concepts in the first column with the correct sentences in the second column.
 1. speed A.  When the skater is at the top of the track ……  energy is highest. 2. friction B.  The skater’s weight does not influence the speed. 3. mass C.  When still moving the skater has …………  energy. 4. kinetic energy D.  The skater is moving faster in the beginning. 5. potential energy E.  On a smooth track the skater will go faster. 6. thermal energy F.   At the end of the skating tour all energy has been tranferred into heat.
###### For correct answers see bottom.

Playground

1. Design a skate track whereby the skater makes a salto and does not fall off the track.
2. Present the skate track to your classmates and explain what you have done to reach your goal.

# GearSketch

#### Every month DiScoro writes about resources that can be used in schools and about inspirational issues. See Services in the Menu for workshops, training etc.

In the Davinci project we used GearSketch to experiment with how gears and chains transmit motion. GearSketch is one of the many resources and programs/simulations available from GoLabz.

It’s always a challenge to come up with interesting tasks that require inquiry and reasoning. Below two tasks where students have to explore both the program as well as features of and patterns within the use of gears.

• Design a combination of gears resulting in a driving wheel showing the hour hand of the clock and another wheel in the gears showing the minutes hand of the clock.

• Compare the two different bicycles and write down at least five (technical) differences.

Task 2b Bicycle with gears
On a modern bicycle you will often find 6–8 gears on the rear wheel and maybe 2-3 gears on sprocket where the pedals are.

• Where must the chain lie when you cycle uphill? Explain your answer.
• Where must the chain lie when you cycle downhill or downwind? Explain your answer.

GoLabz and GearSketch

 Purchase Free Hardware PC , iPad, tablet Requirements browser

# Mechanics: Force Effect

Autodesk Force Effect is an App and webapplication which simulates design concepts from machanics. The App can be used in higher education.

The catchy visualisation of the Force Effect simulations can certainly moti vate the students. It is probably best to use the simulations as an illustrative introduction because the simulations are a simplification of the much more complex rationale behind it. The lecturer should guide the students through the more complex mathematics and mechanics behind the simulations.

 Purchase Free Hardware iPad, iPod touch, iPhone, Android tablet, PC Requirements iOS 5 (or higher)