gaokao 2020 Q17

gaokao · China · shanghai Vectors: Lines & Planes Dihedral Angle or Angle Between Planes/Lines
A square $ABCD$ with side length 1 is rotated around $BC$ to form a cylinder.
(1) Find the surface area of the cylinder;
(2) The square $ABCD$ is rotated counterclockwise by $\frac { \pi } { 2 }$ around $BC$ to position $A _ { 1 } B C D _ { 1 }$. Find the angle between $A D _ { 1 }$ and plane $ABCD$.
(1) $4\pi$ 
A square $ABCD$ with side length 1 is rotated around $BC$ to form a cylinder.

(1) Find the surface area of the cylinder;

(2) The square $ABCD$ is rotated counterclockwise by $\frac { \pi } { 2 }$ around $BC$ to position $A _ { 1 } B C D _ { 1 }$. Find the angle between $A D _ { 1 }$ and plane $ABCD$.
Paper Questions
Q1 Q2 Q3 Q4 Q5 Q6 Q7 Q8 Q9 Q10 Q11 Q12 Q13 Q14 Q15 Q16 Q17