Ask the Experts - All Questions

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Why are the rockets launched only in the morning? Does earth's momentum or atmosphere has anything to do with it?
- asked by: Kumar Alok
Can a rainbow appear at night?
- asked by: Jason
What is a Synchrotron and how does it work?
- asked by: Akash
What do u mean by eddies current or eddies?
- asked by: fahadpk02
What is canonical variable and canonical transformation?
- asked by: suguna
When and how did scientists discover that there was no oxygen in space?
- asked by: Fran Corrigan
How does the mass of the sun vary over time?
- asked by: Michael Heenan
How does the neutron possess a negative value of magnetic dipole moment though it is a neutral partical.
- asked by: irshad
Who developed the 60hz power system in America, and why?
- asked by: Dalton Watson II
What does the power rating of a microwave oven tell you? The higher the power rating the more microwaves are emitted?
- asked by: Simon Foster
What are the functions of the primary and secondary circuits within an x-ray tube?
- asked by: Nancy Keckler
If one penny and a stack of ten pennies are dropped at the same time in a beaker full of water which will sink first?
- asked by: Nicole Litvin
What are the complete properties of plasma and the probability of plasma being applied in advanced technologies?
- asked by: Brandon Webb
How far from Earth is Halley's Comet (February 2005)?
- asked by: Scott Mabrito
Why is that the mass of a pendulum has no effect on its swing period?
- asked by: Sharleen
What causes the hiss when a droplet of liquid lands on a hot surface?
- asked by: Joey
How fast would the Earth need to spin before it fell apart?
- asked by: Bali
What is the difference between an invariant quantity and a conserved quantity? Any examples?
- asked by: Ryan Leong
I have been told that the sun burns off about five feet of its surface height per day. Is this true?
- asked by: Johnny
Why is our solar system and galaxy virtually flat instead of spherical?
- asked by: Keith DeLong
What kind of vehicles use eddy current braking systems and considering that the opposing force they create decreases as the vehicle decelerates, are frictional brakes always required as a back up system?
- asked by: Alice Danielson
Does moonlight fade fabric?
- asked by: Alexis
How fast and far would a space ship have to travel in order to establish a 1 second disparity between its time and time on earth?
- asked by: Peter Stephenson
What keeps a frisbee stable during flight?
- asked by: Tom Martin
How does a flourecent tube light work? How would you measure the amount of light that comes out of a flourecent tube light?
- asked by: Yaseen Ghaffar
Why do planets or other bodies not display ion tails as they pass close to the sun, as comets do?
- asked by: Patrick
How are the complex numbers used in fluid dynamics?
- asked by: Naz
Is an error in a measurement caused by parallax, an example of random or systematic uncertainty?
- asked by: Stella Nicolson
Can a laser be used to create a plasma, and can that heated plasma then be used for propulsion? How much energy would a laser need to accomplish this?
- asked by: Derek Fell
Why does the e/m (charge/mass) ratio of electron not change and why does this change in case of protons , from element to element ?
- asked by: Aashish Aroon
Does distilled water boil at the same temperature that regular tap water does?
- asked by: Dale Everett
What is the smallest object visible with a light microscope?
- asked by: Mike Carrigan
What effect/relation do inner core fires of planets (eg earth) have on their gravities?
- asked by: Ravi
What are the differences in filling a party balloon with helium or nitrogen?
- asked by: Robert
Can one make a magnet into a Mobius strip?
- asked by: bob
Which element has the highest number of isotopes?
- asked by: Brad
How do bubbles exist? I know that they are essentially just surface tension. At the same time, it takes soap to create a bubble, but soap eliminates the surface tension of water. With this information, how could it be possible for a bubble to exist? They seem to be contradictory objects.
- asked by: Joey Duncan
Do the three laws of thermodynamics apply in any way inside an atom?
- asked by: Peter
Why doesn't gold rust or tarnish?
- asked by: Nick Thoman
I'm guessing a microwave oven would wipe clean and/or destroy a video tape. But what is actually happening?
- asked by: Kevin Phillips
Does linearly polarised light give the same interference pattern when passed through Young's double slit apporatus.
- asked by: Richard Coppack
Can light be slowed down to a complete stop?
- asked by: Jon
How was the earths orbit changed by the giant impact that formed the moon?
- asked by: Richard Collier
What is: Population Inversion, Different types of Coherence and Optical Pumping and how are they related?
- asked by: Gurudas Mandal
What is a difference between Amorphous and Glassy solids?
- asked by: Vinodkumar V Nair
What is a thermocouple
- asked by: sree
Carl Sagan wrote about laser retroreflection from the moon which indicated a wooble there. Has anything else been done with it? Is there any reference books I can get about it???????
- asked by: Dolores Urquidi
Is it possible to use pulsating magnetic fields of a specific frequency at a predetermined temperature to excite hydrogen molecules in efforts to increasing their brownian motion to the extend of overcoming the inter-molecular strong nuclear forces and produce fusion?
- asked by: Ning Hu
What is spin glass?
- asked by: Ananda Kumar Das
Is it possible to determine the neutron kinetic energy by using the cerenkov effect?
- asked by: J. mohseni
Is the earth shrinking in size ?
- asked by: HARALD STOVER
What is the difference between magnetism and eletromagnetism
- asked by: Lenny Ace Johnson
How does a diamond get its shine?
- asked by: J. Bose
Does a 100% reflective mirror exist?
- asked by: Howard Anderson
Why are the primary and secondary coils of a transformer wrapped on an iron core that passes through both coils?
- asked by: Chantelle Morris
What wavelength is a black light?
- asked by: Stuart Tsubota
What is the time interval between a high tide and a low tide?
- asked by: Maile
How does a Faraday shield prevent RF radiation from passing through it, and are all frequencies attenuated by an equal amount with a given screen.
- asked by: mack paulk
Is polorized light deflected by a magnetic or electric field, and if not, why not?
- asked by: mack paulk
How does color affect the way a liquid heats up?
- asked by: Alyssa Rogers
Has an experiment ever been performed that tests the propagation of gravity?
- asked by: Michael Trotta
What is the difference between impedance and reactance?
- asked by: Silvy Thomas
What is an isotropic medium?
- asked by: Ogunsade Adedolapo
Why are lower frequencies(in sound)less directional than higher frequencies?
- asked by: James
What is a leaf electroscope?
- asked by: Akash
What is the difference between evaporation and vaporization?
- asked by: Ron Wilcox
How fast must a steam turbine spin to generate electricity? ie. is there a minimum rotational velocity?
- asked by: Justin Karakai
Why is caesium (Cs) the standard element used in atomic clocks?
- asked by: Curtis Mitchell
How does one convert from Lumens on light bulbs to watts so that I can determine how efficiently the watts are being converted into light rather than heat?
- asked by: Walter_Bradley
Why water is less dense as a solid than as a liquid?
- asked by: Wing
How would a physicist describe their theory of symmetry?
- asked by: Nicole Robinson
In an eddy current brake (spining disc and eclipse magnet) what effect do slits cut into the disc have?
- asked by: Mike K
Why don't magnets do work?
- asked by: jen
What is the hubble space telescope's design lifetime?
- asked by: gregory dowdlist
Why does an inflated balloon travel in circles instead of in a straight path when its air is released?
- asked by: rebecca
Is there a relationship between electrical conductivity and viscosity since both properties increases with temperature?
- asked by: Evelyn
I am from England and have just been travelling through Mexico where every night just after the sun went down a very bright star could always been right above where the sun set. We called it the 'Western Star' what is it's real name?
- asked by: Alex Wilson
How do nebulae get their colour?
- asked by: Jen
Why is smoke silver in colour?
- asked by: Adati Tarfa
How does temperature affect the resonance of a solid such as a tuning fork?
- asked by: Marlene
Can you explain the thermodynamics of Fuel cell,in terms on how much work,heat and efficiency it produces compared to gasoline engine cars.
- asked by: Javier
How many years does it take the Milky Way to spin around once? How did the scientists figure this out?
- asked by: Pauline
How is it possible for virtual particles to become real in a vacuum if enough of an electrostatic force is supplied?
- asked by: Andrew Austin
What is the density of tritiated water (HTO)and that of tritiated heavy water(DTO)?
- asked by: NS ANAND
What is the average size of an asteroid?
- asked by: Erin
Who invented the fiber-optic cable?
- asked by: Andrew Kaplan
What would happen if a nuke was detonated in the earth's core?
- asked by: Antonio Pires
What is the furtherest known object in the sky? If you know, what is it called, and how far away is it?
- asked by: Juli
Why does chalk make the scretching sound on a chalkboard?
- asked by: Allison
How do solar cells produce electricity?
- asked by: Andrew
Do stars ever collide? What happens if they do?
- asked by: adrian mc phillips
Why doesn't the moon rotate while other moons do?
- asked by: Robert H. Davidson
Is it true that magnetic fields never do work on charged particles? If so, how can one permanent magnet pick up another that's lying on a table?
- asked by: Noah Segal
Can atomic mass of an element be measured in zero gravity enviroment?
- asked by: Arthur
When Apollo 11 splashed down, the Navy divers immediately handed the crew something. What was the item?
- asked by: Pamela Lim
What is nonlinear dynamics? What are its applications?
- asked by: husni mubarak
What wavelengths of radiation are emitted when antimatter collides with matter?
- asked by: Xiao Li
If the universe were indeed finite, let's say it was a sphere, what might space-time be like at the edges?
- asked by: Julie Book
How does a quantum well laser work? Please give a bibliography.
- asked by: Giriraj Sharma
Which is more dangerous-alternating current or direct current?
- asked by: shuchi
What are the uses of photoacoustic spectroscopy?
- asked by: Sureshkumar
What is synchrotron radiation?
- asked by: C Efeoglu
How is electricity generated from a battery cell and how does it get exhausted ?
- asked by: SciFreak
when we look at the quark table for charmness, strangeness we see that; c quark has charmness of +1, but strangeness of s quark is -1. Why is that? Do not we expect s quark has strangness of +1?
- asked by: sezgin
What is modal dispersion?
- asked by: Sunny
Can color affect the rate in which an ice cube melts?
- asked by: alonzo juhans
How does a changing magnetic field generate an electric field?
- asked by: Kevin Wong
Is there another type of wave that can be used to see the surface of Jupiter through the gas clouds?
- asked by: Jeff Wallington
When a magnet is held above a paper clip the clip rises to the magnet. The clip now has more potential energy. Where does that Energy come from?
- asked by: Kelly Cook
Does stokes law for spheres moving through a viscous liquid apply to parachutes moving through the air?
- asked by: Daniel Sheehan
What is the significance of Millikan's oil drop experiment? What practical developments did it make possible?
- asked by: Susan Spence
How does a solar radiometer work? Why does it spin?
- asked by: Robert Yu
Who would be today's top physicist?
- asked by: Ann K.
How does the Boomerang work?
- asked by: George Wo
How is rolling friction determined?
- asked by: Mary C.
What is the difference between Schrodinger picture and Heisenberg picture?
- asked by: tariq
How can you find south by using the stars?
- asked by: Angela
Why is it that most metals are silver in colour?
- asked by: John Nutschnig
Why do smaller flat screen displays use LCD technology and larger ones PLASMA.
- asked by: James Cawte
If there is no free oxygen on jupiter, then how come there were explosions & flames when a meteor struck it some years back?
- asked by: URJIT
Why are waves formed on a sea ?
- asked by: Pranesh S
How many volts does a bolt of lightning have?
- asked by: Michael Bogart
How many light years are we from the Milky Way galactic center?
- asked by: Tanis Oviedo
Photoeletric Effect: Is there any relationship between work function and electrons in conduction band? Is there any connection between work function and ionization energy?
- asked by: fanny
Does conversion from matter into energy always implies some heat generation?
- asked by: Julian
What is the connection between the chaos theory and astronomy?
- asked by: Rielle
What is a Kuiper Belt? What is behind it?
- asked by: Jessie
What are the key points of writing the scientific letter of reference on a research (the criticism on a research)?
- asked by: Oleh Zadoretskyy
What is quantum confinement?
- asked by: Jose Rajan
If a single photton of light changed mediums, would it refract or change direction?
- asked by: Dan Mill
How does laser thermometer work?
- asked by: Andrew
Is there such thing as Magnetic Mirror?
- asked by: Jeff A.
Are cosmic rays part of electromagnetic spectrum and do they have even higher frequency and shorter wave length than gamma rays?
- asked by: Jordan Mifsud
I've heard about an experiment that shows that the gravitational field can be shielded. Can you give us more details ?
- asked by: Stefan
How is liquid nitrogen produced in liquid nitrogen plant in your university?
- asked by: Haseena
Can a ring laser giro detect the earth’s rotation?
- asked by: Morris Anderson
Could you give some reference on continuous refraction when a wave encounters a medium which refractive index is continously changing?
- asked by: nin

Can light travel through a thin layer of medium without being absorbed and reemitted? If so, shouldn't some photons travel through that medium at speed of light in vacuum?
- asked by: Albert
What is the difference between Coulomb's law and Gauss's law?
- asked by: Joe
Why are there no green stars?
- asked by: Julian Krishna
Im an avid hockey player, and I've always wondered how do the different flexes of sticks effect the velocity of a puck being shot?
- asked by: Matt Wall
What is 'Poynting Vector', and how is it significant?
- asked by: Devlin Baker
How is chaos theory related to cosmology/astronomy?
- asked by: Sinitral Chainz
What is X-Ray Crystallography and how is it used, or how was it used, to study molecular structures?
- asked by: Ken Howel
Bright lights (such as car headlights) often appear to be surrounded with a pattern of fine spikes of light which often contain various colours. What causes this effect?
- asked by: Larry Bird
How does the Lorenz attractor work, what does it represent?
- asked by: Jheremizhs
How and why does the eye of a hurricane form?
- asked by: Ana Stoica-Constantin
Has the Higgs Field been linked to gravity?
- asked by: Laney
What is the etimology of the words nematic, smectic, and cholestric in study of liquid crystal polymers?
- asked by: Kay Shams
Why are snow flakes symetrical?
- asked by: Amanda McIlhone
Where is the closest black hole to the earth? How far away is it?
- asked by: krishna
What is the difference between Lasers and LEDs?
- asked by: Dark Mark
What is the estimated ratio between matter and anti-matter in the universe and where can we find anti-matter?
- asked by: Gadi Tsiony
What is QCD? What is the difference between the charge and color ?
- asked by: Maria
My son William is doing a science fair project for 6th grade. He tried using different light bulbs to power a solar car. The incandescent bulbs (infrared, regular white and UVA) worked but flourescent bulbs did not although they had the same light (lumens). He wanted to know why?
- asked by: Mary Ann Franden
How many sub atomic particles have been discovered to date?
- asked by: Kevin
What is the history of relativity before Albert Einstein?
- asked by: Marty Levitt
What is the locality and non-locality principles mean? And what is the EPR paradox?
- asked by: rasyid
How do Bizzaro Swirls (from your eStore) work?
- asked by: Ryan
Why do bubbles form hexagons when they touch each other?
- asked by: Brian Chewning
What is emittance?
- asked by: Meng Lu
I was reading that diamonds were formed at about 50,000 atmospheric pressures. This made me wonder, what is the highest natural pressure within the earth, where is it? How does this compare with high pressure enviornments created in labs or manufacturing?
- asked by: Mike Siekkinen
On a conductor carrying a static charge, why does the greatest charge density occur at the points that have the greatest curvature?
- asked by: Dwight Propp
Does sound travel faster in ice or water, for the same volume of both the things?
- asked by: Tj
How do we find the half-life of radio active elements?
- asked by: rearabiloe
Is it possible to measure the speed at which quantum tunneling occurs?
- asked by: Stephen
Why does thunder sound first high pitched and then lowpitched?
- asked by: Justin Mancinelli
What is Attosecond Physics? and are there articles or books about this subject?
- asked by: Dr. Raouf Wasfy
Can you explain branes?
- asked by: mr.lo
Why is the photon in a lasing material emitted in the same direction as the stimulating photon?
- asked by: Phong Tran
How does MRI work?
- asked by: Mark J.
What does a forensic physicist do/study? What schooling is required in order to become a forensic physicist?
- asked by: Alison
Can flights to the moon be launched at any time?
- asked by: gemma
Is the rate of expansion of the universe faster than the speed of light?
- asked by: Harry K. Youmans
What happens when electricity is passed through a magnet
- asked by: Sebin
How, where, when and who first converted water into hydrogen?
- asked by: Brittney
What is Rydberg's Law?
- asked by: Andrew Jones
Is there a current experiment to detect gravitrons, the gravitational field particles?
- asked by: Daniel Landi
What is displacement current?
- asked by: jamshed
Why we take point charges in coulomb's law? What will be the effect if we do not take point charges?
- asked by: anoos
What is the definition of heat?
- asked by: Kashif Khan
Einstein described gravity as a distortion in space-time. If this is so how do gravitons fit in?
- asked by: David Wade
What would be the minimum safe distance from a supernova? What kind of negative effects would planet Earth feel if it were too close?
- asked by: Jeff Mansfield
What is the meaning of XYZ written together?
- asked by: Anita Thomas
Who was the first African American woman to receive her Ph.D in physics in the U.S. and when did she receive her degree?
- asked by: Megan Galbraith
my neice has done an experiment that shows that waves travel faster in deeper water and slower in shallow water. Why?
- asked by: Tim SHields
Is it possible that the whole universe can be explained in terms of a cellular automaton?
- asked by: Hammad A Siddiqi
What were some of the scientific tools used in the 17th century to determine the mass of the earth.
- asked by: cesar Martinez
Why are electron neutrinos much easier to detect than the other types?
- asked by: Jeffery I Buchman
Would anti-matter chemecally react to other anti-matter the same way as matter reacts to other matter?
- asked by: George
If friction is independant of surface area, why do racing cars have wide tires?
- asked by: nick preece
Is there a limit to the resolution capability of telescopes as technology improves?
- asked by: Kathleen Stetka
What would happen if two black holes collided. Would they just become one? Would any xrays/gamma rays be released?
- asked by: Craig P
Can someone tell me about the scope of Adaptive Optics in the Industry.? What is the current research going on in it and what is its future when viewed from the perspective of an Electrical Engineer?
- asked by: Richard Clark
I love Physics, but i dont understand what matter-antimatter is? Could you explane it to me?
- asked by: Craig
How astronomers know that our galaxy is not centre of universe?
- asked by: Srinivasa Murthy
Is the atmosphere actually layered or does one property blend into the next?
- asked by: Matt Schonert
How can we tell the difference between a red shift due to gravity and a red shift due to acceleration away from us?
- asked by: James Ward
Is there a limit to the resolution capability of telescopes as technology improves?
- asked by: Kathleen Stetka
Why is it hot before it rains?
- asked by: Christopher Alec A. Maquiling
how long does it take the sun's photon's to go from the center of the sun to the surface.
- asked by: terry deto