Force
Force, commonly, a “push” or “pull,” more properly defined in physics as a quantity that changes the motion, size, or shape of a body. Force is a vector quantity, having both magnitude and direction. The magnitude of a force is measured in units such as the pound, dyne, and Newton, depending upon the system of measurement being used. Unbalanced force acting on a body free to move will change the motion of the body. The quantity of motion of a body is measured by its momentum, the product of its mass and its velocity. According to Newton's second law of motion (see motion), the change in momentum is directly proportional to the applied force. Since mass is constant at ordinary velocities, the result of the force is a change in velocity, or an acceleration, which may be a change either in the speed or in the direction of the velocity.
Two or more forces acting on a body in different directions may balance, producing a state of equilibrium. For example, the downward force of gravity (see gravitation) on a person weighing 200 lb (91 km) when standing on the ground is balanced by an equivalent upward force exerted by the earth on the person's feet. If the person were to fall into a deep hole, then the upward force would no longer be acting and the unbalanced force of gravity would accelerate the person downward. If a body is not completely rigid, then force acting on it may change its size or shape. Scientists study the strength of materials to anticipate how a given material may behave under the influence of various types of force.
There are four basic types of force in nature. Two of these are easily observed; the other two are detectable only at the atomic level. Although the weakest of the four forces is the gravitat...
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...led, are attractive and account for a wide range of physical phenomena, such as friction, surface tension, adhesion and cohesion of liquids and solids, viscosity, and the discrepancies between the actual behavior of gases and that predicted by the ideal gas law. Van der Waals forces arise in a number of ways, one being the tendency of electrically polarized molecules to become aligned. Quantum theory indicates also that in some cases the electrostatic fields associated with electrons in neighboring molecules constrain the electrons to move more or less in phase.
electromotive force, abbr. emf, difference in electric potential, or voltage, between the terminals of a source of electricity, e.g., a battery from which no current is being drawn. When current is drawn, the potential difference drops below the emf value. Electromotive force is usually measured in volts.
The linear momentum of a particle of mass, m, moving with a velocity, v, is defined to be the product of the mass and velocity: p=mv
Whenever there is an interaction between two objects, there is a force upon each of the objects. When the interaction ceases, the two objects no longer experience the force. Forces only exist as a result of an interaction .The forces in the motion of a running person are propulsion (this is the force applied onto the muscles for a forward motion causing acceleration, wind (this is the force put onto the runner by the wind [can cause acceleration or deceleration] depending on the direction), drag (this is the force of air resistance which can cause deceleration and gravity (witch effects everything it is keeping us for flouting around and why things hit the ground. In this assessment we used all three of newton’s law3 for example every object in a state of motion remains in that state of motion unless an external force is put onto it. The relationship between an object's mass m, its acceleration a, and the applied force F is F = ma and for every action there is an equal and opposite
The amazing transformation the study of physics underwent in the two decades following the turn of the 20th century is a well-known story. Physicists, on the verge of declaring the physical world “understood”, discovered that existing theories failed to describe the behavior of the atom. In a very short time, a more fundamental theory of the ...
...ys that for every action there is an equal and opposite reaction, and this is also displayed when a bat hits a ball. The bat exerts force on the ball, just as the ball exerts force on the bat. This force can sometimes even be enough to break the bat, like in the illustration below.
The acceleration of a body or object is directly proportional to the net force acting on the body or object and is inversely
Momentum is defined as the product of mass and velocity on a body. It is a vector quantity and is measured in kg.m.s-1 (M.Mann, 2013).
Kirkpatrick, Larry, and Gerald F. Wheeler. Physics: A World View. 4th ed. Orlando: Harcourt College Publishers, 2001.
According to mechanical physics, a force is an effect that may cause a body to accelerate. Also as stated in Isaac Newton’s second law of motion, force is a vector quantity (has magnitude and direction) that is proportional to the product of the mass of a body and its acceleration.
Fowler, Michael. “Modern Physics.” Lecture. Mass and Energy. 1 Mar. 2008. Web. 13 Oct. 2013.
The force on a small object is bigger than the same force acting on a
In our text we began our study of physics with motion because motion is a dominant characteristic of the Universe (Kirkpatrick, 21). In class we learned that speed is the distance traveled divided by the time taken, s=d/t. The definition of velocity is very close to that of speed except that direction of an object is also taken into account.
Most objects are made of matter with equal amounts of positive and negative charge. Objects with the same # of positive and negative charges are electrically balanced, or neutral. Electric force is observed only when the balance of charge on objects is disturbed.
This electric field pushes the charge carriers downwards. If the material is a conductor, the electric field pushes the free electrons downwards (negative y direction). As a result, a large number of charge carriers (free electrons) are accumulated at the bottom surface of the
Though there is still much to know about the nature of electricity, there is a basic understanding of its essence. As mentioned previously, electricity is a form of energy from the existence of charged particles. To thoroughly understand electricity, it is imperative to first analyze electric force. Coulomb’s law summarizes the electric force between two objects. Coulomb’s law is written as F= k_e (|q_1 ||q_2 |)/r^2 , where ke is 8.9875 x 109 N x m2 /C2. As shown in the equation, the separation distance of the charged particles is on the bottom of the fraction. This means that a greater distance would yield a lower force. Electricity can be classified in two different ways: static electricity or current electricity. In static electricity, there is a transfer of electrons between