by Ron Kurtus
Readers have sent in a total of 162 comments and questions on Experiments issues. They are listed according to date.
You can read them to further your understanding of the subject.
|First year chemistry lessons||General||Namibia|
|Finding volume of irregular objects||Fluids||Ghana|
|What are the different variables?||Friction||South Africa|
|Using plastic strips in an electroscope||Electroscope||India|
|Aluminum versus plastic strips in electroscope||Electroscope||India|
|Wants to make a rubber band powered device||General||India|
|Science fair project classification||General||Guatemala|
|When is website updated?||General||USA|
|Experiment with waterwheel in oil||General||Barbados|
|Wants to know about Electrical Engineering||General||Nigeria|
|Coefficient of friction experiment||Friction||South Africa|
|Measuring weight in water doesn't seem to work||Fluids||USA|
|Static electricity and hair color||Static Electricity||USA|
|Questions would help learning||Fluids||Vanuatu|
|Does fiction depend on area of contact?||Friction||Philippines|
First year chemistry lessons
February 19, 2015
how to carry out accurate and quality first year chemistry 1A ,Introduction to biology and physics practicals in the LABORATORY.
Robson - Namibia (25773)
See the lessons in Chemistry for the basics. We'll be having Chemistry experiments soon.
Likewise, lessons and experiments in Biology will be coming son.
Best wishes for success in your studies.
Finding volume of irregular objects
February 11, 2015
i send u greetings.my question is, how is the experiment "finding the volume of an irregular objects "important 1).globally
(2).in Education (3).in the world of work.Thank you.
- Ghana (25761)
A major purpose in wanting to find the volume of an irregular object is to help determine the material that the object is made of.
For example, if you have an irregular object that is supposed to be 100% gold, you can find its volume and compare its weight with the weight of the same volume of gold. If there was some other material mixed with the gold, the weight would be different, proving that it is not 100% gold.
Knowing this method can be important in education, as well as in business.
What are the different variables?
February 8, 2015
What would be the dependent, independent and controlled variable for this experiment.
2)What would be the Discussion and analysis of results
Please would you respond to me as quickly as possible, It is very urgent.
Mahd - South Africa (25755)
An independent variable does not depend on other variables. It is one that you can vary. For example, in measuring the coefficient by sliding the object down a ramp, the angle of the ramp is an independent variable.
A dependent variable is one that depends on other factors. It is one that is observed or measured. For example, the force of sliding friction depends on the coefficient of friction and the normal force pushing the objects together.
Controlled variables are quantities that you want to remain constant and must observe them as carefully as the dependent variables. For example, you can see if changing the weight will change the coefficient of friction.
I hope that helps. best wishes for success in your experiment.
Using plastic strips in an electroscope
January 29, 2015
sir would you please clear my doubt that whether plastic strip do show repulsion in case of aluminium strip in an electroscope
kindly help me
isha - India (25733)
The strips or leaves in an electroscope should be thin enough to move from the opposing electrical charges. But also, they must conduct the electrons, so that the charges can collect on the leaves. That is why very thin aluminum or gold foil is used.
The problem with something like plastic is that it does not conduct the electrons, so that they cannot collect on the surfaces.
It is a good experiment to compare an electroscope with aluminum foil versus one with thin plastic strips. You will probably see the plastic strips do a poor job of repelling.
Aluminum versus plastic strips in electroscope
January 27, 2015
hlo sir plz hlp me
i want to know that when the aluminium strips of electroscope replaced by plastic strip then what will happen?
isha - India (25726)
If the aluminum strips are very thin, they should work much better than plastic strips. Why don't you try an experiment using aluminum and plastic strips to compare them? That would be a good experiment.
Wants to make a rubber band powered device
January 16, 2015
ok so i have to make some rubber-band powered devices that solve 1 technical difficulty in total and the main force of the device should come from a rubberband and we also cannot use direct manual force.
can you help me??
- India (25705)
Take a look at images of rubber band powered devices to get some ideas. I hope that helps.
Science fair project classification
August 16, 2014
My name is Maria and I'm doing a science fair project. I'm doing the "Shrinking Styrofoam Cup" which consists of putting a styrofoam cup in an oil pressure. The sure particles, the pressure, and vapor cause the cup to shrink. I have a question, is this physical science: chemistry? Or just physical science: physics?
Reply as soon as possible please :)
Maria - Guatemala (25277)
It sounds like a good science fair project. It probably could be classified as Physics, since it concerns the properties of the material. But it could also be considered under chemistry since it is changing a material. So, wither one would work.
Best wishes for success in your project.
When is website updated?
August 12, 2014
I would like to know when this website was last updated and the author of this website. I couldn't seem to find it anywhere and I need to cite this website for a school science project. If you don't mind, e-mail me back as soon as you can so I can continue with this part of the project. Thank you so much for your time and cooperation.
Fallon - USA (25259)
Each lesson page has a date after the author's name. If the page has been revised, it indicates that.
It is usually better to cite individual subjects, but if you want to cite the whole website, the author is Ron Kurtus and the updates are ongoing.
Best wishes fro success in your science project.
Experiment with waterwheel in oil
May 17, 2014
Hello my name is Shaun Durant and I have a question pertaining to leverage. I'm working on a science project of sorts its a table top model. Basically its an artificial waterfall submerged in a lighter density fluid "oil". I'm attempting to capture the falling water with a waterwheel, however I'm not sure what dimensions will work best since water falls unusually in oil. Is this something your experts can help with? Actually the problem is slightly more complicated, I'd like to send a 30 second video clip of the prototype, this will show exactly what the problem is that I'm having. I've being advise to patent the prototype after its completion, so please, please, be discreet with the video clip. Awaiting your response, thank you for your time.
Shaun - Barbados (24968)
You really should define the purpose of your project. Is it simply to demonstrate how a waterwheel or paddle-wheel would work in a fluid? Or do you want to find the best size or shape of the waterwheel?
I understand that the water would not fall directly down in oil.
Feel free to send the video in a replay email, and I'll take a look at it. I certainly won't show it to anyone.
Wants to know about Electrical Engineering
March 24, 2014
About electrical engineering
holy - Nigeria (24809)
Right now we do not have a section on Electrical Engineering. However, our section on Electricity and Magnetism can give you a start on the basics you will need to know.
Best wishes for success in your studies.
Coefficient of friction experiment
March 16, 2014
Precautions for coefficient of friction experiment
Adolf - South Africa (24790)
It is a good idea to perform a friction experiment several times to get an average reading. If you are sliding objects, using a spring scale, you should be slide slowly and regularly.
Adding weight to the object being slid and them comparing calculations helps to get a good value.
You can also try different methods to find the coefficient of friction between two materials.
Best wishes with your experiments and measurements.
Measuring weight in water doesn't seem to work
March 8, 2014
Hello! I am doing this experiment with my first grade son and all of the items are weighing the exact same in and out of the water! We had assumed that they would for sure weigh less in the water when they are sinking and displacing the water above. We have tried heavier objects, larger objects, and other variations and no matter what I use the results are the same: the rock is weighing 4.6 oz on land and 4.6 oz totally submerged in water. Am I missing something? My son badly wants to be a scientist and I don't want to lead him down a wrong path of understanding science just because I'm doing something wrong! He wanted to do this due to his curiosity of why he can lift his brother in the pool but not on land. ANY help would be so much appreciated!
Megan - USA (24589)
The best way to weigh the rock is to hang it by some string from a spring scale or something similar both in air and in the water. There should be a difference in weight. Otherwise, I'm not sure why you are getting the same weight in and out of the water.
I will have to add a drawing to the experiment to clarify the method.
It is good that your son is curious, because that it the first step in becoming a scientist.
Static electricity and hair color
November 30, 2013
My name is Mrs. Latoya Bush, I have a nine year old daughter who is doing a science fair project on static electricity and hair color, and would like to get information and use it for as a resource.
1. can you please explain static electricity?
Johnae - USA (24235)
See Controlling Flyaway Hair from Static Electricity for information about the subject. Your daughter should be able to understand the material.
By brushing or combing a person's hair with a plastic comb, you can create static electricity. Red hair is usually very fine and results in flyaway hair more that thicker hair, such as black hair.
I hope that helps. Best wishes on her project.
Questions would help learning
November 1, 2013
this experiment is very good and it works. do you think that this will help the students if there are no questions that will contribute to the students learning and understanding? Excuse my poor English
kathrian - Vanuatu (24160)
Thank you for your suggestion. I will be adding questions and answers to the various experiments, in order to help the students learn and understand the material.
Does fiction depend on area of contact?
July 24, 2013
Does frictional force depend on the area of contract?
Roberto - Philippines (23884)
For hard flat surfaces, the resistance force of friction is independent of the area of contact. See Standard Friction Equation for information.
However, most surfaces are not perfectly flat or hard. Variations will result in area of contact having a contribution.
Studying how friction varies with pressure, area, and flatness would be a good set of experiments.
Questions and comments
Do you have any questions, comments, or opinions on this subject? If so, send an email with your feedback. I will try to get back to you as soon as possible.
Share this page
Click on a button to bookmark or share this page through Twitter, Facebook, email, or other services:
Students and researchers
The Web address of this page is:
Please include it as a link on your website or as a reference in your report, document, or thesis.
Where are you now?