How can I improve my Experiment plan?

[RemotePhysics]

Homework Statement

Design and experiment to verify the equation for centripetal force F=(mv^2)/r.
Include explanations of the analysis of the experimental results the would confirm the verification, safety precautions

Relevant Equations

F=(mv^2)/r

Just completed my experimental plan for the question above and would like some feeback on what I can improve, and how I can fix any errors in my plan?

Also please do let me know what you would have done differently if you had answered this question.

https://docs.google.com/document/d/1ie6yBuiNWmak-Ag8CjslGunPfltwhPIj73LESe9mMvo/edit?usp=sharing

 

[ProxyMelon]

Well, your setup seems a bit dangerous, hopefully no one gets injured :D

What i think i would do is to get some kind of motor (maybe from an eletric fan) and create a rotating plate, once you have that you can measure what you need with much more precision (you can even make a wooden plate and put a scale on top of it) with ease, for example by placing a small weight held on by a spring (fixed on the axis of rotation on the other end), you should easily be able to evaluate the spring constant and it's elongation, and then get the centrifugal force from there (by calculating static equilibrium).

The main problem with your setup (not counting whirling glass tubes around) is that it's fairly hard to reproduce the same conditions each time

 

[hutchphd]

The experiment you propose will verify that F is proportional to $v^2$. How does it address the functional dependence on m and r? Also some method to qualify the accuracy of technique might be good.

 

[RemotePhysics]

Well, your setup seems a bit dangerous, hopefully no one gets injured :D

What i think i would do is to get some kind of motor (maybe from an eletric fan) and create a rotating plate, once you have that you can measure what you need with much more precision (you can even make a wooden plate and put a scale on top of it) with ease, for example by placing a small weight held on by a spring (fixed on the axis of rotation on the other end), you should easily be able to evaluate the spring constant and it's elongation, and then get the centrifugal force from there (by calculating static equilibrium).

The main problem with your setup (not counting whirling glass tubes around) is that it's fairly hard to reproduce the same conditions each time

This is a good idea. The idea of using a glass tube and string came from a teacher resource online!

 

[RemotePhysics]

The experiment you propose will verify that F is proportional to $v^2$. How does it address the functional dependence on m and r? Also some method to qualify the accuracy of technique might be good.

Interesting. How do you propose I address the dependence on m and r? There are not too many resources online that show how to verify the equation without using some expensive specialised machine.

 

[hutchphd]

I would like to hear your ideas. The r part is experimentally easier within your experimental design .

 

[RemotePhysics]

I would like to hear your ideas. The r part is experimentally easier within your experimental design .

I presume that I could address the dependce on r by varying the length of the rope? And that I could address the dependence on m by varying the amount of washers thus changing the mass and the circular motion force (F).

Here is a video of the experiment which may make my setup easier to understand.


Also is the way i have laid out my document easy to understand or could I improve it?

 

[RemotePhysics]

@ProxyMelon Whats your thoughts on #7? How would you tackle this?

 

[ProxyMelon]

Are you talking about the period calculation?

 

[RemotePhysics]

Are you talking about the period calculation?

I was trying to suggest a way to " address the functional dependence on m and r". Not really too sure how to do it. How would you answer this question? Not many resources on how to prove the formula at all on the internet.

 

[ProxyMelon]

Well, if you wish to evaluate the dipendence on one variable you should try to do your best in order to keep the other variables fixed, clearly it would be quite hard to keep the period T fixed while you change various ropes/masses.

Despite it being hard to actually perform, you could consider using more than one rope passing through the tube?

Or simply substitute the g force (the washers) with another mass whirling aroung could do

 

[RemotePhysics]

Well, if you wish to evaluate the dipendence on one variable you should try to do your best in order to keep the other variables fixed, clearly it would be quite hard to keep the period T fixed while you change various ropes/masses.

Despite it being hard to actually perform, you could consider using more than one rope passing through the tube?

Or simply substitute the g force (the washers) with another mass whirling aroung could do

Nice, in terms of what I have already written in the document. Do you think that it would suffice considering that the question is only worth 6 marks? Would you say that what I have written answers the question?

 

[ProxyMelon]

Well, I am surely not a teacher so I can't really help you with that.

In my opinion what you should do is ensure that anyone reading you paper would be able to understand what's going on clearly, even if you are not able to solve a specific problem be sure to point it out and to propose possible solutions.