b) Chọn hệ Oxy
Có : \(\overrightarrow{N}+\overrightarrow{P}+\overrightarrow{F}=m\overrightarrow{a}\leftrightarrow\overrightarrow{N}+\overrightarrow{P_1}+\overrightarrow{P_2}+\overrightarrow{F}=m\overrightarrow{a}\left(1\right)\)
Chiếu (1) lên Oy có: \(N-P_2=0\Leftrightarrow N-Pcos45^o=0\rightarrow N=mgcos45^o\)
Chiếu (1) lên Ox có :
\(Psin45^o-F_{ms}=Psin45^o-\mu mgcos45^o\)
=> a = \(g\left(sin45^o-0cos45^o\right)=10sin45^o=5\sqrt{2}\left(m/s^2\right)\)
b) P=mg = 0,1.1=1N
\(P_1=Psin45=mg.sin45=\frac{\sqrt{2}}{2}\left(N\right)\)
\(P_2=Pcos45=mgcos45=\frac{\sqrt{2}}{2}\left(N\right)\)
