9/7/09NC Science Olympiad Coaches Clinic Under Pressure NC Science Olympiad Coaches Clinic October 3, 2009 Dr. David G. Haase Professor of Physics NC State University

9/7/09NC Science Olympiad Coaches Clinic Overview Event Description General event rules Overview of the subject matter Resources Examples of questions or activities Time for Questions

9/7/09NC Science Olympiad Coaches Clinic Event Description Students will demonstrate their knowledge and skill related to the physics of fluids. Experimental tasks and questions including calculations

9/7/09NC Science Olympiad Coaches Clinic Under Pressure New event about the properties of liquids and gases Not being used in Nationals Replaces Physics Lab C Division B (middle school) and Division C (high school)

9/7/09NC Science Olympiad Coaches Clinic General Event Rules Teams of two 50 minutes Combination of questions and activities May bring non-programmable calculator and one (1) 8.5 x 11 in page of notes front and back. Students must bring and wear goggles during the event. No other resource materials or electronic devices allowed Where appropriate, materials data will be supplied, e.g. the density of a certain solid. No caustic or flammable liquids will be used in this event Disclaimer: In all disputes the rules published on the NCSO web page are the controlling authority.

9/7/09NC Science Olympiad Coaches Clinic Content Matter Liquids and gases Density = mass/volume Floating and sinking

9/7/09NC Science Olympiad Coaches Clinic Content Matter Pressure P = Force/area Atmospheric pressure Pressure as a function of depth in a liquid P = ρ g h Barometer

9/7/09NC Science Olympiad Coaches Clinic Content Matter Bernoulli’s Principle: P 1 + (½)ρ v ρ g h 1 = P 2 + (½)ρ v ρ g h 2 Buoyancy Buoyant Force F buoyant = ρVg Archimedes principle

9/7/09NC Science Olympiad Coaches Clinic Content Matter Pascal’s Principle Hydraulic and pneumatic devices

9/7/09NC Science Olympiad Coaches Clinic Content Matter Charles’s Law (law of volumes) Boyle’s Law

9/7/09NC Science Olympiad Coaches Clinic Content Matter Surface tension Capillary action Thermal expansion in liquids (Why do icebergs float?) Viscosity and viscous forces

9/7/09NC Science Olympiad Coaches Clinic Resources Physics: Principles and Problems Conceptual Physics by Paul Hewitt MIT Open Courseware – Physics of Fluids High School Physics Lab The comPADRE Digital Library Physical Sciences Resource Center

9/7/09NC Science Olympiad Coaches Clinic Fluid Activities Measure the density and determine the composition of an unknown object using Archimedes method Predict whether an object will sink or float Measure the rate of air flow with a water manometer made with clear plastic tubing Design and aluminum foil boat that can flow at a certain amount of mass Calculate the amount of water displaced by a floating object

9/7/09NC Science Olympiad Coaches Clinic Fluid Activities Straw and potato Demonstrate how to blow out a candle with Bernoulli effect Measure the relative densities of two liquids Predict the water pressure needed to fill a tank

9/7/09NC Science Olympiad Coaches Clinic Fluid Activities Estimate the weight of an automobile by measuring the tire tracks. Lift an object by inflating a balloon Measure or estimate the flow rate of liquid through a tube Calculate the pressure on a submerged object Measure the relative viscosity of two liquids Measure the compression of a gas under changes in temperature or pressure

9/7/09NC Science Olympiad Coaches Clinic Fluid Activities Design a hot air balloon to lift a certain weight Design a device to measure changes in pressure Observe a fluid phenomena and explain its physical basis Build a paper airplane or parachute

9/7/09NC Science Olympiad Coaches Clinic Conclusion Questions? How can we help you prepare? How are you going to coach your students for this event? Session evaluation

9/7/09NC Science Olympiad Coaches Clinic Questions or Comments?

9/7/09NC Science Olympiad Coaches Clinic