Anhtam89
Cau 1:
a) Thiet Lap Gia Toc phap tuyen
xet 1 cd chuyen dong tren duonf tron tam O tai thoi diem t chat diem o vi tri M, vec'to V=MA , tai thoi diem t' = t +deltat o vi tri M', V'= M'A' Ki' hieu( Delta= d)
co' a = lim dv/dt ve MB=V' lay diem C/ Mc =V' tren phuong AM
dV= V'-V=MB-MA=AB=AC+CB
=> a= lim (AC+CB)/dt
dat an = lim CB/dt
co' goc' CMB = goc' MOB = d0
xet' tam giac MCB = (pi-d0)/2
khi t' -> t suy ra d0->0 suy ra CB co phuong huong vao tam O
an= lim CB/dt= lim (2MC.sin(d0/2))/dt= lim(V'.d0)/dt
an = lim V'.dS/(dt.R)= Lim (V'/R)( lim dS/dt= V.V/R= V^2/R
b) PT chuyen dong va quy dao cung chuywen dong tron
x= R.cos(wt+fi)
y= R.sin(wt+fi)
pt quy dao
X^2+ Y^2=R^2
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