Inside Balloons: How does air exerts pressure? - PhET

<strong>Inside</strong> <strong>Balloons</strong>:<strong>How</strong> <strong>does</strong> <strong>air</strong> <strong>exerts</strong> <strong>pressure</strong>?Name: _____________________________Learning objectives: Students will be able to describe and draw what <strong>air</strong> looks like at a microscopic level. Students will be able to explain how <strong>air</strong> applies <strong>pressure</strong> and predict how various changesaffect the <strong>pressure</strong>.Activity:1. Discuss your ideas about “What the word <strong>pressure</strong> means?” with your partner.Write down your ideas after discussion.2. Explore the Gas Properties Simulation.Draw a picture of what you think the <strong>air</strong>inside this classroom looks like if youcould zoom really, really close in on the<strong>air</strong>.Use words to help describe what ishappening in this picture.__________________________________________________________________________________________________________________________________________________________________________3. The <strong>air</strong> inside a balloon will apply <strong>pressure</strong> on the walls of the balloon.The <strong>air</strong> inside the box in the Gas Properties Simulation is applying <strong>pressure</strong> on the lid.Suppose you were inside the box in the simulation, pushing up on the lid. <strong>How</strong> is that similarto, or different than, what the <strong>air</strong> is doing?__________________________________________________________________________________________________________________________________________________________1

__________________________________________________________________________________________________________________________________________________________4. <strong>Balloons</strong> can pop!<strong>How</strong> many different ways can you find to blow the top off of the container in the sim? _____For each method (up to 3), record the reading on the <strong>pressure</strong> gauge when the top flew off,describe your method and your ideas about how the <strong>air</strong> is able to blow the top off.Method#1Pressurereading =Describe your methodDescribe what’s changed about theparticles are hitting the lid2Pressurereading =3Pressurereading =5. Looking at your observations from Question #4, which factors do you think affect <strong>air</strong><strong>pressure</strong>? Justify your answers with evidence from the simulation.______________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________2

6. Compare the 4 cases and observations about <strong>pressure</strong> below.Starting conditionThe ComparisonsHotterparticlesParticles insmaller boxMore,hotter particlesLowHighLowHighTemperature Temperature Temperature TemperatureRegular size box Regular size box Half size box Regular size boxLOWPRESSUREThe ObservationsMEDIUMPRESSUREMEDIUMPRESSUREVERY HIGHPRESSUREUse the simulation to develop a General Explanation forhow <strong>air</strong> particles apply <strong>pressure</strong>that can explain the differences in the cases above.Write your general explanation here:Use your general explanation to explain observations for each case:3