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

Why don't the proton and the electron in a hydrogen atom collapse?
- asked by: J. Viranga Perera

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

What is the physical explanation of the fact, that the electric field is zero inside a conductor?
- asked by: imran

What is the Discrete Fourier Transform?
- asked by: Ozair Sajid

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

Why is it dangerous for a person to stand near a very highly charged object?
- asked by: Julie

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 the particle structure of a flame?
- asked by: Lindsay Hill

What is spin glass?
- asked by: Ananda Kumar Das

How can you make oil sink in water?
- asked by: Anita

How do you find an objects resonant frequency?
- asked by: Tim Pope

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

In a series circuit with two or more bulbs, which bulb lights first when the circuit is closed?
- asked by: Eric Gardner

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

Currently,where are the Voyagers 1 and 2 space probes?
- asked by: Sara Irina Md. Rijaluddin

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

Vacuum is a dielectric. Where does the impedance to charge flow come from?
- asked by: Vijayakrishnan

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

If you lit a flame in an oxygan atmosphere in space, what direction would the flame burn in?
- asked by: Matthew Wilson

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

Does ozone occur naturally at ground level and is it safe to breathe?
- asked by: Bill Bryan

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

How does a Crookes Radiometer work? Will it work if the vessel is evacuated? What did Maxwell have to say on the matter?
- asked by: Darcy Fawcett

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

Why are left turns on a cycle easier than right? Also, when I run track I notice that everyone always runs counterclockwise.
- asked by: Robert Crosby

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

What are quantum numbers? And how many are there?
- asked by: Sharma

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

If an orbiting artificial satellite were to slow down, what would happen?
- asked by: Christopher Alec Maquiling

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