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tam0009
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Pushing a block -- Car project
To begin w/ i would like to say that my knowledge on the subject of physics is fairly minute. I have a project assigned to me in my Intro to engineering class where my group has to build a car out of legos and later race it competitively. We have to make preliminary design reports were my group will discuss the various design aspects of our car. We split the work between team members and I have to find the ideal weight for our car. The most obvious choice is as light as possible, but that might not be exactly true in my case. As part of our obstacle course, our car will be required to push a 1kg block some distance. Our car is going to be powered by an electrical lego motor provided to us as part of the project. That's about all i know about the motor. We did, however, run a few tests on it one day in lab where we attached a weight to the motor and timed how long it took for the motor to move that weight 1.143m. From which we determined the rpm of the motor during that time period. I thought that being as we lifted the weight straight from the floor (there was a string attached to a fixed point on the wheel that picked the weight up as it turned) i could solve this problem with the work-energy theorem by finding the [tex]\Delta[/tex]W then dividing that by the distance to find force (w=F*D). well i found force, but that evidently is not the number i need because between the different trials (with different weight) the force will vary according to the mass of the object lifted (I checked these force measurements by finding tension T was indeed equal to F). Now being as the F varies between the different cases its obviously the information I'm looking for here (being as I am trying to figure out the capabilities of this single motor), so any well you all could give to point me in the right direction would be great... I added a zip document showing the what we found in lab (just to add any other relevant information due to the properties of the motor as V[tex]\rightarrow\infty[/tex] A[tex]\rightarrow[/tex]0, and the D of the wheel was 0.01905m)
To begin w/ i would like to say that my knowledge on the subject of physics is fairly minute. I have a project assigned to me in my Intro to engineering class where my group has to build a car out of legos and later race it competitively. We have to make preliminary design reports were my group will discuss the various design aspects of our car. We split the work between team members and I have to find the ideal weight for our car. The most obvious choice is as light as possible, but that might not be exactly true in my case. As part of our obstacle course, our car will be required to push a 1kg block some distance. Our car is going to be powered by an electrical lego motor provided to us as part of the project. That's about all i know about the motor. We did, however, run a few tests on it one day in lab where we attached a weight to the motor and timed how long it took for the motor to move that weight 1.143m. From which we determined the rpm of the motor during that time period. I thought that being as we lifted the weight straight from the floor (there was a string attached to a fixed point on the wheel that picked the weight up as it turned) i could solve this problem with the work-energy theorem by finding the [tex]\Delta[/tex]W then dividing that by the distance to find force (w=F*D). well i found force, but that evidently is not the number i need because between the different trials (with different weight) the force will vary according to the mass of the object lifted (I checked these force measurements by finding tension T was indeed equal to F). Now being as the F varies between the different cases its obviously the information I'm looking for here (being as I am trying to figure out the capabilities of this single motor), so any well you all could give to point me in the right direction would be great... I added a zip document showing the what we found in lab (just to add any other relevant information due to the properties of the motor as V[tex]\rightarrow\infty[/tex] A[tex]\rightarrow[/tex]0, and the D of the wheel was 0.01905m)
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