Accueil Mecanique Electricité Optique Chimie Matière

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PCCL © 2017

Attractive action
exerted by remote /
Remote action exerted
by the Earth on an object in its neighborhood: weight of a body.
The kinetic energy: the relationship giving the kinetic energy of a solid
translation is:
- The Universe in motion and time
- Movements and forces
Relativity of motion
Principle
of inertia
The constituents of
matter: neutrons, protons, electrons.
- The mass and the
gravitational interaction, Newton's law.
astronomical scale
1. Vector speed of a point of
the solid
Actions on a solid examples of
effects (maintaining balance, setting in motion of translation, rotation,
deformation)
Action of a
magnet, a current, a very short needle.
Proportionality of
the field value B and the current in the absence of magnetic media.
Laplace's law : management,
direction, value of the force: F = I.l
Conversion of electrical energy into mechanical energy. Role of Laplace forces. Observation of the effect associated with the reciprocal motion of a circuit in a magnetic field: conversion of mechanical energy into electrical energy.
Possible effects of a force whose point of application moves.
W Work unit: the joule (symbol : J). Expression of the work of the
weight of a body.
- Work: a mode of energy transfer
In a terrestrial reference, experimental study of free fall of a body near the Earth's work weight : W Energy
interpretation, definition of the kinetic energy of a solid translation.
Potential energy of a strong interaction with the Earth ; Special case situations are located near the Earth. Relationship : E Conversion of potential energy into kinetic energy in the case of free fall.
Some other effects of work
received (elastic deformation, temperature rise, changes in
physico-chemical).
Work can produce a given rise
in temperature of a body. A similar rise in temperature can be achieved by
transfer of energy in another form: heat transfer; microscopic appearance.
Vibrating mechanical
system associated with a system for coupling with the air
Highlighting modes of
vibration by sinusoidal excitation: fundamental mode, harmonic
quantification of their frequency.
Highlighting modes of
vibration by sinusoidal excitation.
Observing the
reflection of a wave on a fixed obstacle; qualitative interpretation of
the shape of the reflected wave.
Wave of any shape
between two fixed obstacles: recurrent imposed by the distance L between
the two fixed points and the speed
Standing wave between
two fixed obstacles: quantification methods ; relation
n
Qualitative observation of the phenomenon.
Musical acoustics and
physics of sound
I Sound level: the decibel sound,
L = 10 log
Range: octaves, tempered scale.
- Temporal evolution of mechanical systems
Qualitative connection
between
ΣF
Comparison
Introduction
Acceleration :
_{
Δ}_{t
à}_{
}_{0} (Δv_{G} /Δt)
= dv_{G}/dt
;acceleration vector (direction, sense, value).
Role of the mass.
Force of gravity, the notion of uniform gravity field. - Fall vertical friction
Application of
Newton's second law of motion to a vertical drop: forces applied to the
solid (weight, buoyancy, fluid friction force) differential equation of
motion resolution by an iterative numerical method, the original scheme
and asymptotic regime ( called "permanent"), speed limit; notion of
characteristic time. - Vertical free fall
Uniformly accelerated
rectilinear motion, acceleration independent of the mass of the object.
- Movements of projectiles in a uniform gravitational field
Application of
Newton's second law to the movement of center of mass of a projectile in a
uniform gravitational field in the case where friction can be neglected.
- Satellites and Planets
Kepler's laws
(circular or elliptical path).
Pendulum weight,
simple and robust system clock-spring free oscillation : equilibrium
position, deviation from equilibrium, X angle, amplitude, damping
(pseudo-periodic regime, aperiodic regime), pseudo-isochronous period and
small oscillations, natural period.
Return force exerted by a spring. Study dynamics of the system "solid" : choice of repository, balance of forces, under the second law of Newton, differential equation, analytical solution in the case of zero friction. Natural period.
Present, through the
documents most diverse real-life situations where the time evolution is of
particular importance: seismic waves, mechanical vibrations, movements
swings, Earth-Moon laser, increasing the speed of transport (Train high
speed), increasing the clock frequency of computers, time scale of plate
tectonics, and launch a rocket into orbit satellites, the Mir space
station falling, parachute jumping and the elastic, improving sports
performance, etc..
From the examples
given in operation generate the following definition of a mechanical wave:
Notion of
one-dimensional wave.
Notion of periodic
wave.
v .T = v /N
Diffraction in the
case of sine wave : experimental demonstration.
This part is
considered a revised year-end, around the time measurement. It has no
theoretical knowledge or skills due new. The examples are not exhaustive
and the teacher is free to expand. |