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Latest amazing phenomenon of physics are added here every moment to keep you updated always.

  • Quiz Based on Scalar and Vector

    In physics, mathematical quantities that can be used to describe the motion of objects can be divided into two categories: scalars and vectors. Scalars are quantities that are described by magnitude and vectors are quantities that are described by magnitude and direction. Examples of scalars: speed, distance Examples of vectors: displacement, velocity, acceleration 10 ft is a scalar, but 10 ft NW is a vector. For each question in the following quiz, choose whether the given quantity is a vector or a scalar. Remember that scalars have magnitude, but vectors have both a magnitude and direction. Please select the best answer from the given choices.

  • Quiz Based on Momentum

    Momentum is "inertia of motion." A rolling marble can be stopped easier than a bowling ball moving at the same velocity because the bowling ball has more momentum. Momentum of a moving object is related to mass and velocity. If the mass changes or the velocity changes, or both, then the momentum changes. Momentum can also be transferred to other objects. This quiz covers momentum questions. Select the best answer from the choices.

  • Quiz BAsed on Force Acceleration and Mass

    This quiz will illustrate the relationship between acceleration, force, and mass. Examples of the relationship between the three will be explored with various examples.

  • Physicists read Maxwell's Demon's mind

    An international research team, including Dr Janet Anders from the University of Exeter, have used superconducting circuits to bring the 'demon' to life. The demon, first proposed by James Clerk Maxwell in 1867, is a hypothetical being that can gain more useful energy from a thermodynamic system than one of the most fundamental laws of physics -- the second law of thermodynamics -- should allow. Crucially, the team not only directly observed the gained energy for the first time, they also tracked how information gets stored in the demon's memory. The research is published in the leading scientific journal Proceedings of the National Academy of Sciences (PNAS). The original thought experiment was first proposed by mathematical physicist James Clerk Maxwell -- one of the most influential scientists in history -- 150 years ago. He hypothesised that gas particles in two adjacent boxes could be filtered by a 'demon' operating a tiny door, that allowed only fast energy particles to pass in one direction and low energy particles the opposite way. As a result, one box gains a higher average energy than the other, which creates a pressure difference. This non-equilibrium situation can be used to gain energy, not unlike the energy obtained when water stored behind a dam is released. So although the gas was initially in equilibrium, the demon can create a non-equilibrium situation and extract energy, bypassing the second law of thermodynamics. Dr Anders, a leading theoretical physicist from the University of Exeter's physics department adds: "In the 1980s it was discovered that this is not the full story. The information about the particles' properties remains stored in the memory of the demon. This information leads to an energetic cost which then reduces the demon's energy gain to null, resolving the paradox." In this research, the team created a quantum Maxwell demon, manifested as a microwave cavity, that draws energy from a superconducting qubit. The team was able to fully map out the memory of the demon after its intervention, unveiling the stored information about the qubit state. Dr Anders adds: "The fact that the system behaves quantum mechanically means that the particle can have a high and low energy at the same time, not only either of these choices as considered by Maxwell." This ground-breaking experiment gives a fascinating peek into the interplay between quantum information and thermodynamics, and is an important step in the current development of a theory for nanoscale thermodynamic processes.

  • New Definition of the Colorfulness of Photon

    In SALEH THEORY, we believe on the helical motion of photon, of which r is the gyroradius around an imaginary axis. This means that the photon has two simultaneous motions: rectilinear motion at constant speed and rotary motion at constant angular velocity.The visible spectrum is one of the concepts that have attracted much comment. In SALEH THEORY the distinction of spectrums is due to the gyroradius; and its changes induce the colorfulness. In fact, the increase of the gyroradius means reciprocally the widening of the wavelength. For example, the long wavelength of the red spectrum is a result of the high value of its gyroradius r, while for the blue spectrum, it’s the opposite.

  • The verity of spectrums; the diversity of color of photon; the different wavelengths; how to explain it?

    Light and its nature have caused a lot of ink to flow during these last decades. Its dual behavior is partly explained by Double-slit experiment of Thomas Young - who represents the photon’s motion as a wave - and also by the Photoelectric effect in which the photon is considered as a particle. However, Einstein himself writes: "It seems as though we must use sometimes the one theory and sometimes the other, while at times we may use either. We are faced with a new kind of difficulty.

  • Periodic Table Quiz

    here are many periodic tables with structures different than that of the standard form we use today. Within 100 years of the creation of Mendeleev’s table in 1869 it has been calculated that atleast 700 other periodic table versions were introduced.

  • Quiz Contest by Physics Forum

    Time to test your scientist photo recognition skills! As always please post your score in the comment thread at the end.

  • Capillary Action

    Water can work against gravity, moving up narrow tubes in a process called capillary action.

  • About the Pictures of The Milky Way galaxy

    We don’t have any real pictures of the Milky Way galaxy. Most non-illustrated images of the entire Milky Way spiral are actually of another spiral galaxy called Messier 74. It’s impossible to take a full photo of the Milky Way’s spiral structure because it’s about 100,000 light-years across, and we’re stuck on the inside.