Teacher Notes


Balancing Bird
Publication No. 12293
IntroductionThe balancing bird will yield hours of entertainment and learning. Students can even calculate the center of gravity of the balancing bird. Concepts
MaterialsBalance, electronic or triplebeam, 0.1 g
Balancing bird with stand Calculator Metric ruler ProcedureDemonstration
Experiment
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Correlation to Next Generation Science Standards (NGSS)^{†}Science & Engineering PracticesUsing mathematics and computational thinkingDeveloping and using models Constructing explanations and designing solutions Disciplinary Core IdeasMSPS2.A: Forces and MotionMSPS2.B: Types of Interactions HSPS2.A: Forces and Motion Crosscutting ConceptsCause and effectStructure and function Patterns Stability and change Performance ExpectationsMSPS22: Plan an investigation to provide evidence that the change in an object’s motion depends on the sum of the forces on the object and the mass of the object DiscussionIn order to find the center of gravity of the bird with the weights in it, the center of gravity of the xaxis and the center of gravity of the yaxis must be found. These values can be represented by the following equations: X_{center} = (x_{A}m_{A} + x_{B}m_{B} + x_{C}m_{C})/m_{total} where x_{A} is the x coordinate of point A and m_{A} is the mass acting at point A (the weight). The total mass of the bird and weights is m_{total}. ReferencesTipler, P. A. Physics for Scientists and Engineers; Worth: New York, 1991; pp 278–279. 