Кинематика материальной точки

                                                                                                                                                                                                                                                         прямолинейное

                                                                      по скорости                                                                       движение                               по траектории                

                   равномерное                                                              равнопеременное                              криволинейное

   U - const                                                                    a - const                                                                 V               V

  =                                                    ;   Ux=U0x+a                                                                                                       2                                                                                                                                                                                                                                                            a-тангенциальное ускорение, отвечает

    ; x= x0+Sx                              ;                                                                 1                             за изменение скорости по величине. 

V                                    x                                       a                                         S           a>0                                                          R      а-норм.ускорение-по направлению

                  U=f(t)          x0           x=f(t)                           a>0,a=f(t)                               S=f(t)                         а= √а²+а²           

                         t                                     t                                      t                                            t                         Частный случай крив.движения по окружности

Sx                                                                                          a<0

               Sx=f(t)                                                    U                                                 a<0                        U               a_n=a_ц      

                         t                                                               a>0    U=f(t)                         U

                                                                                          a<0                                                                 U

                                                                                x                             t

                                                                                           a>0

                                                                               x0           x=f(t)

                                                                                                         t

                                                                                      a<0                             




ДИНАМИКА – изучает причины

движения и его изменения




           МАССА-физическая величина являющаяся                                                           основные понятия           СИЛА – это физическая величина,являющаяся мерой

мерой: а) количественной, б) инертной,                                                                                                                                                                                                                                                   механического воздействия тел или полей, в резуль-

в) гравитационной, г) энергетической                              Инерциальная система отсчета – которая не                                                                                                                            тате которого тела приобретают ускорение или                

[m]- кг, скалярная величина                                                   подвержена внешнему воздействию                                                                                                                           меняют форму или размер. [F]-Н, вектор

основные законы




I - з-н  Ньютона  Закон инерции                                              II – з-н Ньтона  Основной закон динамики                           III – з-н  Ньютона

-равнодействующая                           F_1,2 = F_2,1

Если сумма всех сил, действующих на тело                       Ускорение тела прямопропорционально                                                                                                                              Действие равно противодействию

равна нулю, то тело находится в состоянии                      сумме сил и обратнопропорционально

покоя или движется равномерно прямоли-                       массе.   

нейно.                                                                                                                                          F₁




                                                                                                                                                 M                              F              F = F₁ +F₂

                                                                                                                                                                     

                                                                                                                                                                      F₂

З – н Всемирного тяготения



Сила взаимодействия между телами прямопропорциональна массам тел и

обратнопропорциональна квадрату расстояния между ними