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Brandon Davidson
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<< Mentor Note -- Two threads on the same subject have been merged >>
I am a junior enrolled in IB Physics at the standard level at my high school. As a part of the curriculum we must perform an Internal Assessment (IA) which involves performing an experiment and performing calculations and it also includes a typed paper.
The format of the question for your experiment is "How does x affect y?" For my experiment I decided to formulate the question; "How do different surfaces at an incline affect the time it takes for an object to roll down the incline?"
For the experiment my independent variable, the surfaces on the incline will be cardboard, carpet, cloth, plastic wrap, and wood. The angle of the incline, the displacement the object rolls down the incline, and the object (a marble) will be kept constant. I plan to ultimately find the coefficient of kinetic friction for each of the surfaces by collecting raw data for time. Then I'll use the equation s=ut+(1/2)at² to find the acceleration of the marble on the different surfaces. Next I would use the acceleration and mass to find Net Force.
This is where I get a little confused. Would I utilize similar triangles and vectors to create the new horizontal component since there is an incline and create the equation [Net Force + (Weight)(sinθ) - friction = ma] ? θ would be the angle of the incline. From there would I simply go on to find the coefficient of kinetic friction by using the coefficient of kinetic friction formula involving normal force and the friction I would have found from my previous equation?
Would there also be a vertical component however since the marble is rolling and not stationary on the incline? I am asking for any help with my confusion I can get as well for any tips regarding anything I may be doing wrong with the setup of the experiment or anything I should change. Thanks.
I am a junior enrolled in IB Physics at the standard level at my high school. As a part of the curriculum we must perform an Internal Assessment (IA) which involves performing an experiment and performing calculations and it also includes a typed paper.
The format of the question for your experiment is "How does x affect y?" For my experiment I decided to formulate the question; "How do different surfaces at an incline affect the time it takes for an object to roll down the incline?"
For the experiment my independent variable, the surfaces on the incline will be cardboard, carpet, cloth, plastic wrap, and wood. The angle of the incline, the displacement the object rolls down the incline, and the object (a marble) will be kept constant. I plan to ultimately find the coefficient of kinetic friction for each of the surfaces by collecting raw data for time. Then I'll use the equation s=ut+(1/2)at² to find the acceleration of the marble on the different surfaces. Next I would use the acceleration and mass to find Net Force.
This is where I get a little confused. Would I utilize similar triangles and vectors to create the new horizontal component since there is an incline and create the equation [Net Force + (Weight)(sinθ) - friction = ma] ? θ would be the angle of the incline. From there would I simply go on to find the coefficient of kinetic friction by using the coefficient of kinetic friction formula involving normal force and the friction I would have found from my previous equation?
Would there also be a vertical component however since the marble is rolling and not stationary on the incline? I am asking for any help with my confusion I can get as well for any tips regarding anything I may be doing wrong with the setup of the experiment or anything I should change. Thanks.
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