Physics

Physics regards the physical aspects of the natural world. It includes topics that deal with forces on different bodies within the universe and phenomena that explain how the universe works.

Asked in Graduate Degrees, Physics, Chemistry, Science Experiments

What is adiabatic calorimetry?

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Adiabatic calorimetry is used primarily for the study of thermal hazards and the consequences of a maloperation during a process, for instance a misfeed or loss of cooling. This is because on larger scales the effective natural cooling rates are negligible in comparison to heat generation, and many large process vessels can therefore be considered to be adiabatic. An adiabatic calorimeter is designed to simulate the thermal behaviour of larger scale chemical reactors, especially when studying uncontrolled and run-away reactions.
Asked in Science, Physics

How can you increase the frictional force between two surfaces?

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The friction between two surfaces can be increased by some or all of the following - Increase the total area of direct contact between the two materials; Decrease minute deviations from direct contact of the materials; Use a superconductor as a "mortar"; Add pressure, weight, or additional mass force pressing down on the surfaces Scuffing or abrasion of smooth surfaces; Application of a "sticky" substance.
Asked in Physics, Electrical Engineering

What is meaning for transient in RLC series circuit?

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In circuit analysis, there is steady state and transient conditions. transient conditions are how the circuit acts immediately following some action (such as turning on power, closing a switch, losing power, etc.). Steady state conditions is everything else.
Asked in Electronics Engineering, Physics, Electrical Engineering

How many ohm's is a 1M5 resistor?

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The plural of 'ohm' is ohms, not ohm's. The alpha-numeric code for identifying the resistance of a resistor is quite straightforward. The letter is used as a multiplier. For example, k = x1000 and M = x1000 000. In other words, k represents kilo, and M represents mega. The position of the letter represents the position of the decimal marker. So, 1M5 represents 1.5 x 1000 000, or 1.5 megohms. 15M represents 15 x 1000 000, or 15 megohms. etc. Similarly, 1k5 represents 1.5 x 1000, or 1.5 kilohms. 15k represents 15 x 1000, or 15 kilohms. etc.
Asked in Physics, Chemistry

What is intermolecular Force?

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Answer: Intermolecular forces are the forces of attraction and repulsion that act between molecules or ions to influence the physical properties of compouds. intermolecular forces are forces that act between stable molecules or between functional groups of macromolecules. Answer: Well the key word is molecule. In a substance like water... There are many water molecules. Water molecules are made up of two hydrogen and one oxygen. When someone says the intermolecular forces they are talking about how each molecules of any substance (in this case "water") interact with each other. Each substance or "thing" that we see has intermolecular forces. Answer: The intermolecular forces means how strong the bonding is between each individual molecule. This strength of the bonds determines whether a substance is a solid, liquid, or gas at room temperature. Intermolecular forces are the forces of attraction between molecules. They include:- Hydrogen bonding, van der waals forces which includes dipole -dipole interactions, dipole -induced dipole interactions, instantaneous dipole interactions (London dispersion forces) Intermolecular force - or physical force - is the attraction between molecules. It attracts the molecules to stick together or repulses the molecules to separate them.
Asked in Physics

What is an example of air pressure in daily life?

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Air pressure is in the tires of a car. And of course, that of the atmosphere itself!
Asked in Physics

What is the relationship between light and heat?

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Heat is a method for the transfer of energy, and light also is a method for the transfer of energy; however, heat is NOT light. All electromagnetic radiation is light, but heat is not electromagnetic radiation; it is heat. When any light in the entire spectrum( whether radio waves, infrared waves, optical light waves, microwaves or gamma rays) contacts matter, it will energize the atoms of that matter and some of that interaction will result in the production of heat and some in the form of electromagnetic radiation (ie some form of light). Heat generated by this interaction will conduct to areas that are colder than the object it is coming from (ie heat from a stove will conduct to air which will spread the heat through convection. A person will feel the heat from the stove as it passes through the air to him at a certain distance- depending on the intensity of the heat source. Infrared radiation is mistaken for heat; it is not heat. It is radiation we can't see that lies below the red band of optical light. Even though we can't see the infrared spectrum it is their like radio waves can be out around us. Heat is also being generated within that frequency band as well. As a matter of fact, ponder this: there is heat being irradiated across the entire spectrum of electromagnetic radiation. Also, if you were tracking the infrared radiation from the ground that was coming from a plane's engines, with a special device you could see the infrared signature but you would not feel any heat. You would have to get up relatively close to that engine to feel the thermal transfer of energy from the engine to the air around it's path.
Asked in Science, Physics, Zoologists

How do zoo keepers use science in their jobs?

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Zoo keepers need to know that exact amount of food and water to keep each animal healthy and the amount of medicines and vitamins the animals need. They need to know how large of a cage to build and how high the walls need to be.
Asked in Physics, Nuclear Physics, Quantum Mechanics

What is mutual annihilation?

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I am not the expert in the field of physics. But I also have not lost my common sense. When electron and positron collide with each other, you get two gamma rays. My esteemed colleague Quirkyquantummechanic has said that the particle and antiparticle are completely converted into energy. Then does this formation of the energy match with the famous equation of the Einstein? The equation goes as E = m c square. Here c is the speed of light. Speed of light is fairly high. Speed of light is roughly 300,000,000 m/s. The square of this number is 90,000,000,000,000,000. As per the theory of my colleague, you get only one gamma ray each from the entire mass of the electron or the positron. It fallows that from the mass of one electron, you get one gamma ray only and from the mass of positron, you get another gamma ray only. Then it is logical that you get one electron from one gamma ray and one positron from another gamma ray. ( The reverse of the process of annihilation.) This is not correct. If you put the mass of the electron and positron, in the equation of the Einstein, you will get much higher energy, than what my colleague has mentioned. (He has mentioned that you will get pair of gamma rays.) This is called as 'emotional' involvement into what you 'believe' in. Science has nothing to do with your 'emotions' and 'beliefs'. You have to explain every thing with logic. Here goes the explanation for the same. It is the 'kinetic' energy of of the electron and positron, that is left as the pair of gamma rays. The electron and positron vanish into 'nothing'. This is one of the greatest invention of the modern time. From particle (electron) you get gamma ray. It fallows that from antiparticle (positron), you get anti-gamma ray. When proton collide with anti-proton, you get many gamma rays, electrons and positrons and neutrinos. Here the kinetic energy has to be much more than electron positron pair. As the mass of the particles is much larger. There has to be 'equal' number of electrons and positrons get generated in the process. They can in turn again get annihilated into nothing and pairs of gamma and anti-gamma rays. The best way to study the annihilation is to study annihilation between neutron and anti-neutron. Here the element of electrical charge is not there. Here you will find that there is complete destruction of the mass into number of electrons and positrons and number of gamma rays. These electrons and positrons will annihilate each other to give you more pairs of gamma rays. So you will get complete destruction of the particle and anti-particle into nothing and only kinetic energy remains there as gamma and anti-gamma rays. If neutrinos are released, then half of them has to be anti-neutrinos. As per Einsteins equation you have E = m c square. if you multiply the equation by minus one, what you get is : minus E = Minus m c square. If you denote the particles as 'm' in the above equation, then you have to denote anti-particle as 'minus m'. It fallows that from anti-particle, you get anti-energy. Even if the 'slightest' mass can be destructed into nothing, then 'all' the mass can be destructed into nothing. This explains the the theory of origin of matter and anti-matter from nothing. Any thing of this sort is bound to generate the emotional reaction. But then the truth only prevails. Here goes the link to the theory. http://www.answers.com/Q/What_is_the_theory_of_creation_of_the_matter_and_anti_matter_from_nothing
Asked in Food & Cooking, Physics, Weight and Mass

What is top pan balance?

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A top pan balance is a weighing device with a flat or curved surface (pan) at the top for holding the item being weighed.
Asked in Physics, Mechanics, Newtons Laws of Motion

A simple net force definition?

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A net force is a measure of the force being exerted on an object; zero net force means an object is at rest or moving at a constant speed. Definition of net force: The net force on an object is the vector sum of all individual forces acting on it.
Asked in Science, Physics

Why does a rubber ball when thrown from a height bounces and then rests?

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First you need to know the forces of energy: elastic force (the potential to be stretched or compressed) normal force (opposite the force of gravity, which is -10Newtons) force of friction (force needed to move an item accross a surface) You also need to know some energies in general: Potential energy ("stored" energy - energy not being readily used) Elastic potential energy (the potential for an item to have an elastic force) kinetic energy (energy built up from moving. Faster = more kinetic energy, vice versa) gravitational energy (The pull of gravity, which is -10N on Earth) energy dissipated (energy lost through heat, sound, vibration, light, or contact with another object) When the ball is held in the air (100% potential energy, since its not moving), or is falling (100% kinetic energy), it has a constant normal force of 10 newtons, while succumbing to earths gravitational pull of -9.8 (10) Newtons. once the ball hits the ground the first time, its kinetic energy (or energy gained from falling [moving]) is converted in elastic potential energy, because it is smacking into the ground and compressing. The ratio for this would be about 75% kinetic energy and 25% elastic potential energy. this means that 25% of the energy used to move the ball has been lost and absorbed by the floor in energy dissipation. Since the ball is always opposite the force of gravity, it must return to its original shape (sphere), so it uncompresses, thus causing it to bounce back up into the air. However, since it is closer to earth and has lost 25% of its energy, it will never go as high as it was released from (unless you intentionally throw it at the ground, but this would give it an additional downward force, causing it to rebound with more energy). Since energy was lost, the ball now has 50% kinetic energy and 50% gravitational energy (because it is not squishing in mid-air). when it hits the ground a second time, it will lose another 25%, and another 25%, and another 25%. If earth had perfect gravity and the world had no friction, the ball would literally bounce forever, but it would soon look like its standing still since we cannot see things on a nano-scale.
Asked in Chemistry, Physics

What is the function of a spectrometer?

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The function of a spectroscope is to measure properties of light. Different materials, even atoms, have different emission spectras.
Asked in Physics, Energy

Mention the different forms of energy?

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The different forms of energy are kinetic, chemical, potential, electrical, electrochemical, thermal, electromagnetic, sound, nuclear, genetical, internal, elastical, anddiscrete.
Asked in Math and Arithmetic, Physics, Density

Formula for finding density?

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Density is the mass of the object divided by the volume of the object. D=m/V
Asked in Physics

Why is no work done no an object when a force acting on the object dose not move?

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It's a play on words (try holding a weight steady at arms length) that's totally dependent on the definition of "work".
Asked in Science, Physics, Chemistry

Is there a phrase of matter below solid?

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Dark matter is a superdense form of matter, where the mass of the material is so great that it collapses down to a tiny point, similar to the effect of a black hole but with nowhere near the force, so technically it could be considered lower than a solid.
Asked in Science, Physics

What is the application of centripetal forces in the daily life?

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You can feel the centripetal force every time you are in a car, and that car goes around a corner. This force has to be taken into account by the driver; otherwise, there can be accidents. Most washing machines have an option for drying the laundry (partially), through an application of the centripetal force.
Asked in Science, Physics, Nuclear Physics

Do protons in a very large nucleus have a greater chance of flying apart?

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Sort of... The general tendency is for a larger atom to be less stable. Above a certain point (after lead) no stable atoms are known to exist. Sort of... The general tendency is for a larger atom to be less stable. Above a certain point (after lead) no stable atoms are known to exist. Sort of... The general tendency is for a larger atom to be less stable. Above a certain point (after lead) no stable atoms are known to exist. Sort of... The general tendency is for a larger atom to be less stable. Above a certain point (after lead) no stable atoms are known to exist.
Asked in Physics, Time

What is less than a picosecond?

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I'm tempted to reply ½ a pecosecond(!) However, I think you're asking what is the next description below pecosecond; it is a femtosecond (10−15 second). There are 1000 femtoseconds in a pecosecond.
Asked in Polar Bears, Physics

Why do the polar regions have high albedo?

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Because snow reflects light more than non-white regions of the Earth and albedo is a measurement of reflectance. By definition white reflects all visible light therefore albedo is greatest .
Asked in Science, Physics, Newtons Laws of Motion

How do you increase the angular velocity of a rotating object?

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Angular velocity just means how fast it's rotating. If youaa want more angular velocity, just rotate it faster or decrease the radius (move it closer to the center of rotation). Just like force = rate of change of momentum, you have torque= rate of change of angular moment Or We can increase the angular velocity of a rotating particle by applying a tangential force(i.e. accelaration) on the particle. Since the velocity of the particle is tangential with the circle along which it is moving, the tangential accelaration will not change the diriction of the velocity(as angle is 0),but will cause a change in magnitude. Thus angular velocity will increase.
Asked in Electronics Engineering, Physics, Electricity and Magnetism, Circuits

What are the factors on which resistance depend?

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It depends on the intermolecular structure of the individual material. It varies for various material. Generalised formula for calculating the resistance of any material is : R = k* L/A Where R = Total Resistance. K = Specific Resistance of the material. A = cross-sectional area of material for which resistance is measured.
Asked in Science, Physics

What is work done by a person in moving a block of mass 2kg on a frictionless floor up to a distance of 5m?

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Scientifically, work is defined as force X distance. In this case, we know the distance (5 m), but we do not know the force. If we knew the original force applied we could calculate the work done. Or, if we knew the acceleration of the 2 kg mass when it was moved we could calculate the force (force = mass X acceleration; Newton's 2nd Law of Motion), then we could use that value to calculate the work done. However, with the information given, it is not possible to calculate the work done in this situation. Perhaps, if we changed the scenario just a bit, we could calculate a different amount of work done. Let's say that by some means a person moved the 2 kg mass upwards, directly away from the center of the earth, to a height of 5 m. Since it is known that the acceleration due to gravity at most places on earth is 9.8 meters/sec/sec, we can calculate the force required to move the object as 19.6 kg.m/s/s (2 kg X 9.8 m/s/s). In the metric system, a kg.m/s/s is known as a Newton (N), so this would be 19.6 N. Using that force value, we can now calculate the work done as 98 N.m (19.6 N X 5 m). A N.m is known as a Joule (J, the metric unit for energy) so our answer would correctly read 98 J. The question displays the natural, instinctive, popular, total fallacy that was logically disproven by Galileo about 500 years ago, and mathematically disproven by Newton about 400 years ago: -- In order to keep an object moving, a force must be applied to it. -- A moving object with no external forces applied to it will stop. This concept makes complete common sense, matches all of our everyday experience, and is totally wrong. The fact is: A moving object continues moving at constant speed in a straight line until an external force acts on it. Work doesn't depend on the mass of the object or the distance it moves. The most massive object imaginable can move through an astronomical distance without any work being done on it at all. The work done by the person is (force with which he pushes) multiplied by (distance through which he maintains that force). If the object is already moving, the person doesn't have to touch it to make it move 5 m. He can just stand there and watch it. If it's not moving yet, then he can push as lightly as he wants, for as short a distance as he wants. The lightest imaginable force will cause the object to accelerate, with acceleration equal to (force) divided by (mass), and then, once it's moving, the force need not be maintained. The force required is: Any force greater than zero, no matter how small. The distance through which the force must be maintained is: Any distance greater than zero, no matter how small. So the work done is: Any amount of work greater than zero, no matter how small. Regardless of the mass of the object, or how far you want to see it move. Moving a larger mass, or moving it a longer distance, does not require more work, so long as the direction is not parallel to gravity and friction is negligible. <<>> simple answer: no net work is needed to move a mass along a level frictionless floor because the force does not operate against gravity. Any horizontal force applied adds to the object's momentum and kinetic energy, then the object will move for ever until another force acts to stop it. Apply a force F for time t, then the impulse Ft is equal to the change of momentum mV. So the speed is a constant one of Ft/m. Work is initially done equalling the kinetic energy imparted to the mass as it is moved. None of this energy is dissipated by friction. Once it has gained momentum, that energy is stored until when it is stopped, at which point the kinetic energy is given up to whatever agent is causing the stop.
Asked in Physics, Energy, Kinematics

Relationship between kinetic and potential and mechanical energy?

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The relationship is that mechanical energy is the sum of kinetic energy plus potential energy. Think of a brick sitting on the edge of a table. The brick has potential energy proportional to the mass of the brick and the height of the table: E = m g h where m = mass, g = gravitational acceleration, h = height If the brick falls off the edge, it will begin to accelerate at g, the rate of gravitational acceleration (9.8 m/s2). If v is the velocity of the brick, it has kinetic energy proportional to the quare of the velocity: E = (m v2)/2 Just before the brick finally hits the floor, all of its potential engergy has been converted to kinetic energy. During the moment of impact, that kinetic energy is converted to noise and vibration.