Physics

A:

According to the Encyclopedia Britannica, in terms of classical theory, electromagnetic radiation refers to energy that flows at the universal speed of light via free space or a material medium in the form of electric and magnetic fields that comprise electromagnetic waves, such as radio waves, gamma rays and visible light. Electromagnetic waves are characterized by their intensity and the frequency of the electric and magnetic field's time variation.

See Full Answer
Filed Under:
  • How are mass and weight related to each other?

    Q: How are mass and weight related to each other?

    A: Mass and weight are closely related because mass affects the weight of an object experiencing the effects of gravity. Weight is the measure of the force of gravity on an object's mass, while mass is the measure of how much matter there is in an object.
    See Full Answer
    Filed Under:
  • What are the Laws of Attraction and Repulsion?

    Q: What are the Laws of Attraction and Repulsion?

    A: The Law of Attraction is the belief that a person's thoughts attract specific things, people and situations into his life. The Law of Repulsion is the belief that the more a person thinks about what he does not want, the more he attracts what he does want. According to SelfGrowth.com, both beliefs support the idea that what a person thinks about, negative or positive, can manifest into reality.
    See Full Answer
    Filed Under:
  • How does a fulcrum work?

    Q: How does a fulcrum work?

    A: A fulcrum is the fixed support or pivot point for a lever, which is a simple machine used to overcome resistance. The lever is a stiff rod or bar, and the location of the fulcrum determines the class of the lever. Levers are useful to increase force, increase speed or change direction of a force, according to HowStuffWorks.
    See Full Answer
    Filed Under:
  • How does gravity affect humans?

    Q: How does gravity affect humans?

    A: Humans evolved with gravity, and gravity affects human physiology and general health. Studies show that weightlessness has a number of negative health effects. Finding ways to mitigate these dangers is essential for long-distance space travel.
    See Full Answer
    Filed Under:
  • Why does a bouncy ball bounce so high?

    Q: Why does a bouncy ball bounce so high?

    A: Bouncy balls bounce high because the material of the ball is extremely elastic and can convert the kinetic energy from the fall into potential energy and back again with very little loss in momentum. Bouncy balls are used in many physics classrooms because they aptly demonstrate conservation of momentum through a highly elastic collision.
    See Full Answer
    Filed Under:
  • Why does rubbing your hands together make them warmer?

    Q: Why does rubbing your hands together make them warmer?

    A: Friction causes the hands to warm up when rubbed together. The greater the amount of friction between two objects is, the more heat is generated.
    See Full Answer
    Filed Under:
  • Does light always travel at light speed?

    Q: Does light always travel at light speed?

    A: Light typically travels at 186,000 miles per second, but scientists have found a way to slow it down to 38 miles per hour. A team at the Rowland Institute for Science has found a new state of matter to help slow light down. Sodium atoms were cooled almost to absolute zero, which is 459.67 degrees Fahrenheit below zero. That’s lowest temperature theoretically possible. They then shot a laser through the extremely cold sodium atoms, which acted like “optical molasses” to slow down the beam of light.
    See Full Answer
    Filed Under:
  • What are some good lab experiments that explain centripetal force?

    Q: What are some good lab experiments that explain centripetal force?

    A: One good experiment that explains centripetal force is the spinning penny. A penny is put inside a balloon, and the balloon is filled with air. Then, the balloon is swirled around until the penny rolls around inside of the balloon. The penny continues to spin even after the swirling stops.
    See Full Answer
    Filed Under:
  • What is the formula for tension in physics?

    Q: What is the formula for tension in physics?

    A: In physics, the tension on a suspended object said to be equal to the weight of the object plus or minus the mass of the object times the acceleration acting on it. In other words, this is the weight of the object plus or minus the force on it, depending on the direction in which the force is acting.
    See Full Answer
    Filed Under:
  • What are examples of noncontact forces?

    Q: What are examples of noncontact forces?

    A: Electricity, gravity and magnetism are all examples of non contact forces. A force is anything that can cause a physical change in an object.
    See Full Answer
    Filed Under:
  • What were the contributions of Archimedes to the field of physics?

    Q: What were the contributions of Archimedes to the field of physics?

    A: The first-century inventor and scientist Archimedes is remembered by physicists as the originator of the principles of mechanics, buoyancy, the lever and the pulley, according to Famousscientists.org. Perhaps his best-known contribution to physics is his discovery of the principle of displacement, which states that objects displace a volume of water equal to their own weight.
    See Full Answer
    Filed Under:
  • What is the difference between kinetic and potential energy?

    Q: What is the difference between kinetic and potential energy?

    A: Kinetic energy is contained in a moving object, while potential energy exists in a stored form. Potential energy can be changed into kinetic energy. Potential energy is ready for release, while kinetic energy is already doing work. The property of a body determines the type of energy it contains.
    See Full Answer
    Filed Under:
  • What are the parts and functions of a theodolite?

    Q: What are the parts and functions of a theodolite?

    A: A thedolite is an instrument used to measure horizontal and vertical distances using lenses and lines. They include several components, such as a telescope, a leveling mechanism, a tripod and a compass. Theodolites are used for surveying and construction to obtain precise readings of landforms so construction projects remain level and plumb with the ground.
    See Full Answer
    Filed Under:
  • What is the difference between an atomic bomb and a nuclear bomb?

    Q: What is the difference between an atomic bomb and a nuclear bomb?

    A: Although both atomic and nuclear bombs derive their immense power from reactions that take place in the nucleus of the atom, they do so in different ways. As the terms are most commonly used, an atomic bomb derives its energy from fission, or splitting atoms, while a nuclear device, or "H-bomb," is driven by fusion.
    See Full Answer
    Filed Under:
  • What is the purpose of a windmill?

    Q: What is the purpose of a windmill?

    A: A windmill uses wind power to create rotational energy for the use in mills, pumps and presses. In the Netherlands, where windmills became important for local economies, they were used to make boards, paint, oil, paper and bread.
    See Full Answer
    Filed Under:
  • What are the advantages and disadvantages of solar energy?

    Q: What are the advantages and disadvantages of solar energy?

    A: There are a number of advantages, such as its renewable nature, and disadvantages, such as the high initial cost, that are worth consideration when it comes to solar power. The overall benefits of using solar energy over other sources of energy, such as the oil, are high, including the fact that it is friendly to the environment.
    See Full Answer
    Filed Under:
  • What causes optical illusions?

    Q: What causes optical illusions?

    A: Optical illusions are caused by a mismatch of what the eyes see and what the brain interprets, according to ABC News. The brain is often tricked into thinking something is moving when contrasting colors are placed in close proximity to each other and repeated. This is why when people want a pattern to move like an optical illusion, the shapes of the pattern are outlined in black and white.
    See Full Answer
    Filed Under:
  • How do convex mirrors work?

    Q: How do convex mirrors work?

    A: Convex mirrors work by reflecting parallel rays of light as if they all emanated from a single point somewhere behind the mirror. The distance between the actual surface of the mirror and this point depends on the level of curvature, with greater curvature resulting in lesser distance. Images in convex mirrors are distorted, with progressive compression of the image away from its center.
    See Full Answer
    Filed Under:
  • What can electromagnets be used for?

    Q: What can electromagnets be used for?

    A: Electromagnets are temporary magnets which have a magnetic field only when current passes through them. Some everyday applications of electromagnets include generators, motors, microphones, loudspeakers and cranes. Electromagnets are also used in scientific equipment such as particle accelerators, mass spectrometers and NMR (Nuclear Magnetic Resonance) spectrometers.
    See Full Answer
    Filed Under:
  • How is light dispersed through a prism?

    Q: How is light dispersed through a prism?

    A: White light bends or refracts as it enters and exits the triangular prism, with shorter wavelengths bending the greatest amounts and longer wavelengths refracting less, resulting in a light spectrum of different colors like a rainbow. Prisms are made of glass or other transparent material and cut so the angle of entry and exit maximize this effect.
    See Full Answer
    Filed Under:
  • What is magnetic force?

    Q: What is magnetic force?

    A: The technical definition of magnetic force is the mechanical force exerted from a magnetic field to a magnetic pole that is placed within that particular magnetic field. Magnetic force involves the simultaneous attraction and repulsion that occurs between particles that are electrically charged and are within the magnetic field itself.
    See Full Answer
    Filed Under: