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Each day readers send in questions and feedback concerning the various lessons in the School for Champions website. A total of 15801 letters have been answered. They are listed according to date.

You can read them to further your understanding of the subjects.

List of next 15 letters





Why is there a gap in a sound wave? Waves India
Can noise cancellation stop tinnitus? Sound UK
Can a person mess with your 6th sense? Senses USA
Why does an apple change color when cut open? Chemistry India
Voltage for vacuum pump Electricity New Zealand
Seeking permission to use image Magnetism Singapore
Getting rid of chronic pain Religion Buddhism Canada
I would like to cancel a transaction Finances UK
How fast is a magnetic impulse? Physics USA
Is time static? Physics Relativity USA
Thoughts on Absolute Zero Physics Thermal Energy USA
Suggested resources Animal Health USA
Pollyannaish drivel Life USA
Using 220 volt device in a 240 volt socket Electricity Australia
Why is nitrogen used in tires? Chemistry USA

Next 15 letters


First 15 letters

Why is there a gap in a sound wave?


June 10, 2017


Why there is an gap between successive compressions and successive rarefactions?

Abhisheka - India (28082)


There is no real gap between compression and rarefaction in sound waves. The wave shape is a continuous sine wave. That means one half of the waveform is compression, followed by an instantaneous change to then become a rarefaction.

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Can noise cancellation stop tinnitus?


June 10, 2017


I have tinitus but am luky as my mind can cancel it out, BUT many people cannot and it drives them mad
can this technology be used for this

len - UK (28083)


It would be nice if noise cancellation would help out, but unfortunately it only cancels external noises. Tinnitus is the perceptions of sounds in your inner ear. There are some medications that can help. See Tinnitus

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Can a person mess with your 6th sense?


June 10, 2017


Can A person mess with your six Sense if so how would you act

Michael - USA (28084)


Our definition of the sixth sense is precognition or being able to sense future events. It is different than being able to read or affect minds.

It is difficult or even impossible for others to mess with your senses, except by some trickery. You can usually tell if you are being tricked.

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Why does an apple change color when cut open?


June 9, 2017


Why apple turns into red colour after cutting into slides?

Maddakam - India (28081)


Apples start to oxidize once they are cut open. That is the reason the colour changes.

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Voltage for vacuum pump


June 7, 2017


hi, i'm looking to buy a vacuum pump from china rated 220v-50hz.can i use it in new zealand which is 240v-50hz with no problems?it has the same plug connection as nz.

dave - New Zealand (28078)


AC voltages vary by about 10% from the listed value. So using a 220V pump at 240 volts should work fine.

Best wishes with your new pump.

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Seeking permission to use image


June 6, 2017


To Whom It May Concern,

I am Christine from the Copyright team of Kydon Learning Systems Institute. My team consists of myself as the Learning Designer and Project Manager, Bing Ying.

We are writing on behalf of Dr So Ping Lam from the School of Electrical and Electronic Engineering, in Nanyang Technological University, Singapore, who teaches EE3010, Electrical Devices and Machines.

As the appointed Content Partner, we are responsible for converting the course EE3010, into a blended learning course which video lectures will be produced and uploaded into NTU’s learning portal. The image on "right-hand rule for electric wire" which we are seeking copyright clearance will be used in the video lectures and students’ lesson materials. Proper citation using APA style will be used for each image to acknowledge your work. The blended course will be launched in January 2018. There will be about 150 undergraduate students who will have access to the learning portal to participate in this course.

We are flexible about restrictions regarding modification and use, so feel free to let us know about it.

Alternatively, if we do not receive your reply, we will add the citation (to mention that the source taken from your website) in our work.

We look forward to your favourable response in granting us the permission to use the image.

Thank you and hope to hear from you soon.

Yours sincerely,

Christine - Singapore (28076)


You have permission to use the "right-hand rule for electric wire" image in your blended course with no copyright or modification restrictions, as long as it includes the proper citation.

Our website is intended for the advancement of learning and education.

Best wishes for success in your blended learning project.

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Getting rid of chronic pain


June 4, 2017


Can you please explain what the 8 attitudes or paths really mean? What is meant by right view, right speech, right intention, etc.etc. I would also like to know how cessation of desires would end chronic physical pain.As an example someone who is born with a painful condition who is still too young to have formed any desires or attachments in life?

Joe - Canada (28073)


You can see explanations of the items in Noble Eightfold Path in Buddhism. They provide the recommended attitudes and conduct for a good life.

Desires and attachments in life seem to concern the mental and emotional conditions. For example, a person with chronic pain should not be envious of those without the pain. Some meditation practices can help a person alleviate pain. However, medication practices still are usually required.

Best wishes for both physical and spiritual health.

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I would like to cancel a transaction


June 3, 2017


i would like to cancel a transaction i made with Newchic

william - UK (28071)


You can check with PayPal UK to see their procedures.

You also should be able to cancel through Newchic online. And finally, you should be able to cancel payment through your credit card company.

Best wishes in cancelling your transaction.

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How fast is a magnetic impulse?


June 3, 2017


Have the effects of magnetism (attraction-repulsion) ever been quantified into speed? How fast is a magnetic impulse?

James - USA (28072)


Magnetic, electrical, and gravitational impulses all move at the speed of light. Typically, a magnetic disturbance will cause an electrical disturbance, resulting in an electromagnetic wave, which also travels at the speed of light.

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Is time static?


June 2, 2017


Love your site, Thank You!

Subject: Relativity/Time
We humans understand time as past, present and future.
The Past is our Memory
The Present is our Current Condition
The Future is our Expectation

Is it possible that Time is static?

We exist in a series of static universes that we register as the duration or "flow" of time.
Even at Planck time there is duration.
Duration is change in the Universe.
By splitting any change into time segments, every change has a beginning, a duration and an ending.
Even the emission of a photon.
It is a static photon, it starts to move, continues to move and stops moving when acted upon or reaching the desired destination (Planck Length).
During the moment when it starts to move there is duration between its static point and its next static point.
There is even duration between the change of static points. Like a buildup to change similar to a potential charge of time. I'll call it a Duriton.
Duritons occur faster than can be measured by our technology. Just because something can't be measured doesn't mean it can't exist.
Our lives are a series of duritons that we register on a massive scale to simulate continuity.
Is it safe to say that we exist in a constant flow of individual duritons, remembering the past as the present?

Thank you.

tMic - USA (28069)


The whole concept of time is difficult and complex.
As far as humans go, the sensing of time seems to vary with age. See Sensing Time. Thus, is time different for different people?

At the quantum level of matter, movement is in "quantum jumps" instead of being continuous. Likewise, since time is related to motion, it too could be in quantum increments. Thus, you could think of time being static in between those jumps. Your idea of a "Duriton" might fit within that area.

In some theories, time is considered a fourth dimension. It can curve just as space can curve.

Keep up the good work in pondering these issues.

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Thoughts on Absolute Zero


June 2, 2017


Subject: Energy/Absolute Zero

"At the physically impossible-to-reach temperature of zero kelvin, or minus 459.67 degrees Fahrenheit (minus 273.15 degrees Celsius), atoms would stop moving. As such, nothing can be colder than absolute zero on the Kelvin scale."

However, is there a scale that measures colder than Zero Kelvin (Absolute Zero)?
Lets call that True Absolute Zero (TaZ)

We know that matter is composed of energy and the reversion of matter to energy is the basis of the atomic bomb. If matter is made of energy then is there a scale that measures energy down to its baseline?

An electron volt (eV) is not a baseline value of energy because we measure fractions of eV. Lets call the baseline value of energy an "Eneron".

Every atom has movement within itself on diminishing scales.
Quarks, Leptons and even Bosons have movement in their spins.
Temperature is movement. Frozen means no movement. True Absolute Zero would imply that all movement has stopped.

Energy implies movement. "Its energetic"
At TaZ (True Absolute Zero) wouldn't energy stop? If an Eneron stops, is it no longer energy. Can it restart without another Eneron acting upon it?

"The first law of thermodynamics, also known as Law of Conservation of Energy, states that energy can neither be created nor destroyed; energy can only be transferred or changed from one form to another."

If the Eneron stops it is no longer energy and thus the first law of thermodynamics is wrong.

In the Universe there exists a potential for everything to eventually and completely freeze over time. Everything in existence reaches true absolute zero and all energy stops. With no energy to initiate movement (heat), there is no action to generate more energy.

Thank you

tMic - USA (28070)


The requirements for Absolute Zero are not only that atoms stop moving or have zero kinetic energy, but also that their internal potential energy is zero. In reality, the binding forces of the atoms would reach zero, such that the particles would fall apart.

Even Quarks, Leptons, and Bosons would not move or spin.

Matter is really not made of "energy". The energy released in an atomic bomb, such that the mass of the material is reduced, is in the form of electromagnetic radiation or photons. These particles do not have a rest mass, but they do have momentum as they move.

An electron volt is the unit of energy equal to the work done on an electron in accelerating it through a potential difference of one volt.

I hope that gives some explanation. Keep up the good work in creatively looking at these Physics concepts.

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Suggested resources


June 1, 2017


Hi there,

I write for Pet Life Today and I’m reaching to share our guide "The State of Pet Healthcare in 2017," which explores pet health care costs and trends, common illnesses, insurance and financial aid options, and more:

We've also created a custom graphic for pet owners on the most common health problems for dogs and cats with symptoms and treatment:

If you like them, I hope you’d consider adding the guide or the infographic (or both) to your pet health resources page.


Cynthia - USA (28067)


Thanks for the suggested resources. I added the links to the Animal Health Resources page.

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Pollyannaish drivel


June 1, 2017


This Pollyannaish drivel reminds me of the adage, "Cheer up things could be worse"

"So I cheered up."

"And sure enough, things got worse."

Stephen - USA (28068)


The way I remember the adage was: I was feeling down and depressed, when I heard this voice saying, "Cheer up, things could be worse." So I cheered up, and sure enough, things got worse." The first part is important.

That is a humorous view on a philosophy concerning your attitude. I believe a positive viewpoint is better than a negative one. Of course, each person can have his or her own philosophy.

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Using 220 volt device in a 240 volt socket


May 31, 2017


i am wondering if you can use an electrical device rated 220 volt in a240 volt socket I live in Australia thank you.

peter - Australia (28066)


The difference in voltages should not matter, since there is about a 10% variation in both. However, if the doesn't match the socket, you would have to get an adapter.

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Why is nitrogen used in tires?


May 28, 2017


Why is it used in tires?

Allen - USA (28064)


Air is made up of 78% nitrogen, so it is already in inflated tires. Pure nitrogen has the advantage of keeping a more stable pressure in the tires over a long run. Race cars use pure nitrogen to avoid pressure changes when the tires heat up during a race.

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