$t=\sqrt{\frac{2h}{g}}=\sqrt{\frac{2.2}{10}}=\sqrt{\frac{2}{5}}s$$v_x=v_o=11m/s$$v_y=gt^2=10.\frac{2}{5}=4m/s$$tan(\alpha)=\frac{v_y}{v_x}=\frac{4}{11}$$=>\alpha\approx 20$
bài 2:$t=\sqrt{\frac{2h}{g}}=\sqrt{\frac{2.2}{10}}=\sqrt{\frac{2}{5}}s$$v_x=v_o=11m/s$$v_y=gt^2=10.\frac{2}{5}=4m/s$$tan(\alpha)=\frac{v_y}{v_x}=\frac{4}{11}$$=>\alpha\approx 20$