wpor_fizika
.docxA particle moving in a circle of radius r with constant speed v is uniform circular motion.
A particle’s position is the location (положение) of the particle with respect (относительно) to a chosen reference point that we can consider to be the origin of a coordinate system.
Compressions, tensions,flexions etc are the form or volume change in compare to its initial state. Such changes are called deformations.
Distance is the length of a path followed by a particle.
For purposes of the current discussion, we assume that two objects are in thermal contact with each other if energy can be exchanged between them by these processes due to a temperature difference
Forces, disappearing with disappearing of deformations, called elastic forces
Heat is defined as the transfer of energy across the boundary of a system due to a temperature difference between the system and its surroundings.
if the total amount of energy in a system changes, it can only be due to the fact that energy has crossed the boundary of the system by a transfer mechanism such as one of the methods listed above.This is a general statement of the principle of conservation of energy.
If we apply Newton’s second law along the radial direction, we find that the net force causing the centripetal acceleration can be evaluated
Internal energy is all the energy of a system that is associated with its microscopic components—atoms and molecules.
Internal energy includes kinetic energy of random translational, rotational, and vibrational motion of molecules, potential energy within molecules, and potential energy between molecules
Kinetic Energy : The energy of motion is called kinetic energy.The faster an object moves, the more kinetic energy it has. The greater the mass of a moving object, the more kinetic energy it has. Kinetic energy depends on both mass and velocity.
Kinetic energy is a scalar quantity and has the same units as work. In the case in which work is done on a system and the only change in the system is in its speed, the work done by the net force equals the change in kinetic energy of the system.
Latent heat of fusion Lf is the term used when the phase change is from solid to liquid (to fuse means “to combine by melting”), and latent heat of vaporization Lv is the term used when the phase change is from liquid to gas (the liquid “vaporizes”).
Moment of Inertia the rotational analog of mass for linear motion The moment of inertia must be specified with respect to a chosen axis of rotation: I=mr2 I has units of kg m2 The further the mass is from the rotation axis, the bigger the moment of inertia.For a given object, the moment of inertia will depend on where we choose the rotation axis (unlike the center of mass).
One mole of any substance is that amount of the substance that contains Avogadro’s number NA= 6.022*1023 of constituent particles (atoms or molecules). [mol-1] where M is the molar mass of the substance. The molar mass of each chemical element is the atomic mass expressed in grams per mole
One of the central features of the energy approach is the notion that we can neither create nor destroy energy—energy is always conserved.
Period T, which is defined as the time required for one complete revolution
The angular velocity is a vector quantity which specifies the angular speed of an object and the axis about which the object is rotating
The average acceleration of a particle is defined as the ratio of the change in its velocity divided by the time interval during which that change occurs: ax=vx/t=(vxf-vxi)/(tf-ti)
The average speed of a particle, a scalar quantity, is defined as the total distance traveled divided by the total time interval required to travel that distance:
The instantaneous velocity is always tangential (касательный) to trajectory. Slope of tangent of position or displacement time graph is instantaneous velocity and its slope of chord is average velocity.
The average velocity vx of a particle is defined as the particle’s displacement ∆x divided by the time interval ∆t during which that displacement occurs v=x/t
The displacement (перемещение) of a particle is defined as its change in position (местоположение) in some time interval.
The five main forms of energy are: Mechanical-When work is done to an object, it acquires energy. The energy it acquires is known as mechanical energy.Heat-The internal motion of the atoms is called heat energy, because moving particles produce heat.Heat energy can be produced by friction.Heat energy causes changes in temperature and phase of any form of matter.Chemical-Fuel and food are forms of stored chemical energy.Chemical Energy is required to bond atoms together.And when bonds are broken, energy is released. Electromagnetic Power -lines carry electromagnetic energy into your home in the form of electricity. Nuclear-The nucleus of an atom is the source of nuclear energy.The sun’s energy is produced from a nuclear fusion reaction in which hydrogen nuclei fuse to form helium nuclei.
The force that counteracts F and keeps the trash can from moving acts to the left and is called the force of static friction fs. As long as the trash can is not moving, fs= F
The heat capacity C of a particular sample of a substance is defined as the amount of energy needed to raise the temperature of that sample by 1°C.
The instantaneous acceleration is equal to the limit of the ratio vx/t as t aproaches 0. By definition, this limit equals the derivative of vx with respect to t, or theme rate of change of the velocity: ax=lim(vx/t)=dvx/dt
The instantaneous speed of a particle is equal to the magnitude of its instantaneous velocity. The rate of change of velocity is acceleration – how an object's speed or direction changes over time (со временем), and how it is changing at a particular point (определенная точка) in time.
The linear momentum of a particle or an object that can be modeled as a particle of mass m moving with a velocity v is defined to be the product of the mass and velocity
The number of moles n of a substance is related to its mass m through the expression
The radial acceleration (centrifugal acceleration ) component arises from the change in direction of the velocity vector
The tangential acceleration component causes the change in the speed of the particle. This component is parallel to the instantaneous velocity
The time rate of change of the linear momentum of a particle is equal to the net force acting on the particle.
The time rate of energy transfer is called power. If an external force is applied to an object (which we assume acts as a particle), and if the work done by this force in the time interval ∆t is W, then the average power
The Zeroth Law of Thermodynamics If objects A and B are separately in thermal equilibrium with a third object C, then A and B are in thermal equilibrium with each other.
Thermal equilibrium is a situation in which two objects would not exchange energy by heat or electromagnetic radiation if they were placed in thermal contact.
Velocity is the measurement of the rate and direction of change in the position of an object.
When a force is exerted on a rigid object pivoted about an axis, the object tends to rotate about that axis. The tendency of a force to rotate an object about some axis is measured by a vector quantity called torque τ (Greek tau).
When a rigid object is rotating about a fixed axis, every particle on the object rotates through the same angle in a given time interval and has the same angular speed and the same angular acceleration.
When an object is displaced on a frictionless, horizontal surface, the normal force n and the gravitational force mg do no work on the object.
Work units –newton· meter (N·m),the joule ( J).