Did the experiment with marble and jello thing...
Once marble didn' move. The next time it moved slightly downward in the cup. the third attemp the marble moved to the bottom center of cup.
Which centripetal force result is correct. Where should the marble move and what direction...or does it stay stationary.
Need help with marble in jello project on centripetal force
Need help with marble in jello project on centripetal force
For centripetal force pjt, what are the final results. Does the marble move in the jello
and where? Had three different results in doing project. What is the correct result?
and where? Had three different results in doing project. What is the correct result?
For the time the marble did not move, perhaps the Jell-O was too thick, as stated in the procedure? You might want to check that all Jell-O cups were made with the same amount of water and if not, run another test.
As for your questions, you should be able to answer them by looking at your data. Hopefully you have done some research on your project theme of centripetal force and understand the concept. Looking at your data and research think about what happened and why. What was your hypothesis for the experiment? Did your results match your hypothesis? Remember your project is not about getting the "right" results; you should be testing a question to find your own answer. If you expected the marble to do something else, you can state this in your conclusion.
Also, leave room for human error in your project. Maybe not all Jell-O cups had the same amount of water added or chilled for the same amount of time. The strength/speed that you spun the cups around with also make a difference. I would suggest doing a little more research and also running the test one more time to see what your results are the next time, keeping in mind all the tiny details.
As for your questions, you should be able to answer them by looking at your data. Hopefully you have done some research on your project theme of centripetal force and understand the concept. Looking at your data and research think about what happened and why. What was your hypothesis for the experiment? Did your results match your hypothesis? Remember your project is not about getting the "right" results; you should be testing a question to find your own answer. If you expected the marble to do something else, you can state this in your conclusion.
Also, leave room for human error in your project. Maybe not all Jell-O cups had the same amount of water added or chilled for the same amount of time. The strength/speed that you spun the cups around with also make a difference. I would suggest doing a little more research and also running the test one more time to see what your results are the next time, keeping in mind all the tiny details.
Different results made us question which was correct
In doing the experiment with the marble in the center of two colored jello,
found that the strength/speed of acceleration forced the marble to move out away from the center; but remained in the middle bottom of the cup.
Was this what should have occured. My hypothesis stated that I expected the marble to move because of Newton's law of motion; but did others have the same results. Did their marble move and where?
found that the strength/speed of acceleration forced the marble to move out away from the center; but remained in the middle bottom of the cup.
Was this what should have occured. My hypothesis stated that I expected the marble to move because of Newton's law of motion; but did others have the same results. Did their marble move and where?
For centripetal force pjt, what are the final results. Does the marble move in the jello
and where? Had three different results in doing project. What is the correct result?
and where? Had three different results in doing project. What is the correct result?
I don't know how others fared with this experiment, but this bit of info from the project introduction should help you out:
"Newton realized that when things move in a circle that the object wants to move out, away from the center of the circle. In our car example, you experienced this circular motion when your parent turns a corner. Your body moves to the outside of the turn, away from the direction of the turn.
So if your body wants to move away from the turn, then what makes you move in a circular path? This is what Newton described as a centripetal force, or a force that makes an object move, or accelerate, towards the center of a circle. Without centripetal force the object would move in a line. In the car example, the weight of the car, gravity and the friction of the road keep you in your seat moving in a circle."
Compare your body in a moving car to the marble in the moving Jell-O cup. By saying middle bottom of the cup, I assume that you mean that the marble moved down to the bottom of the cup without moving horizontally-again think of what happens when you're in the car. You will lean towards the outside of the curve, but you won't be forced to move in any other direction. You sound like you got your expected results for your project, so as long as you can logically explain why and how you got the results you did you should be fine; don't worry about what others got.
"Newton realized that when things move in a circle that the object wants to move out, away from the center of the circle. In our car example, you experienced this circular motion when your parent turns a corner. Your body moves to the outside of the turn, away from the direction of the turn.
So if your body wants to move away from the turn, then what makes you move in a circular path? This is what Newton described as a centripetal force, or a force that makes an object move, or accelerate, towards the center of a circle. Without centripetal force the object would move in a line. In the car example, the weight of the car, gravity and the friction of the road keep you in your seat moving in a circle."
Compare your body in a moving car to the marble in the moving Jell-O cup. By saying middle bottom of the cup, I assume that you mean that the marble moved down to the bottom of the cup without moving horizontally-again think of what happens when you're in the car. You will lean towards the outside of the curve, but you won't be forced to move in any other direction. You sound like you got your expected results for your project, so as long as you can logically explain why and how you got the results you did you should be fine; don't worry about what others got.
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Craig_Bridge
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If you search for "Centripetal Force" you can find some higher level math descriptions such as http://hyperphysics.phy-astr.gsu.edu/hbase/cf.html that may also explain differences in your results.
This equation tells us that the centripetal force you generated by swinging the cup around in a circle increases the faster you swing it as the square of velocity (speed of rotation). In other words double the rate and you quadruple the force.
The equation also tells us that the bigger the circle (bigger radius) the less force.
This force is spread over the surface of the marble which becomes a pressure on the jello which resists the movement of the marble. If all of the marbles were the same diameter and mass (weight) and you made all jello cups from the same batch of jello then they should have the same consistency (sama density and plasticity). The only possible difference might be pressing the marble into the jello at different stages of the jello setting causing some pre-splitting.
This equation tells us that the centripetal force you generated by swinging the cup around in a circle increases the faster you swing it as the square of velocity (speed of rotation). In other words double the rate and you quadruple the force.
The equation also tells us that the bigger the circle (bigger radius) the less force.
This force is spread over the surface of the marble which becomes a pressure on the jello which resists the movement of the marble. If all of the marbles were the same diameter and mass (weight) and you made all jello cups from the same batch of jello then they should have the same consistency (sama density and plasticity). The only possible difference might be pressing the marble into the jello at different stages of the jello setting causing some pre-splitting.
-Craig
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bradleyshanrock-solberg
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In general the same batch of jello should give you roughly the same results, but to ensure that you have to be pretty careful about how you create the jello.
Variations in the heat in the oven, or in the cooling procedure can cause it to "set up" with different strength. So can uneven mixture (sugar content has a rather profound impact on how jello sets up, as does how much liquid was used).
You also want to insert the marbles the same way, at the same time in cooling process and they should all be the same shape, size, weight. You also want to have some way of controlling how fast the cups spin. (eg, you might put them on a turntable at different distances from the center...something controlled by a motor, not by just spinning it by hand)
I would expect that the direction of motion wouldn't be affected by these variables, but whether or not the marble moved and how far it moved would be greatly impacted by these variables.
Variations in the heat in the oven, or in the cooling procedure can cause it to "set up" with different strength. So can uneven mixture (sugar content has a rather profound impact on how jello sets up, as does how much liquid was used).
You also want to insert the marbles the same way, at the same time in cooling process and they should all be the same shape, size, weight. You also want to have some way of controlling how fast the cups spin. (eg, you might put them on a turntable at different distances from the center...something controlled by a motor, not by just spinning it by hand)
I would expect that the direction of motion wouldn't be affected by these variables, but whether or not the marble moved and how far it moved would be greatly impacted by these variables.