③革由接掌大孝 但博学一求宣倒新 South chi na Agricul tural Uni versity 3. Discussion of curve motion Projectile motion O The velocity of particle is dx VocodE d t y vo sin 8o-gt 6 2 The displacement of particle is dt cos dt=vcos 0 . y=v, dt= (vo sin 8o-gt)dt =vo sin 8oot-gtD e p. p h y sic s D e p. p h y sic s D e p. p h y sic s 11 3. Discussion of curve motion • Projectile motion ① The velocity of particle is: ② The displacement of particle is: 0 0 0 0 c o s s i n x y d x v v d t d y v v g t d t        0 0 0 0 0 0 2 0 0 0 0 0 0 cos cos 1 ( sin ) sin 2 t t x t t y x v dt v dt v t y v dt v gt dt v t gt                   0 v 0 x y