Answer:
Displacement after two seconds
= <Dx,Dy> = <42.426, 1.593> m to three decimal places
Explanation:
Given:
arrow shot at 30m/s and 45 degrees with horizontal.
Hit bull's eye after 2 seconds.
Find horizontal and vertical displacements.
Vx = 30cos(30) m/seconds constant velocity
therefore
Dx = Vx*t = 30cos(30) m/s * 2 s = 60 cos (45) = 42.426 m
Vy = 30 sin(45) m/s
Dy = Vy*t + a(t^2) /2
= 30*sin(45) -9.81(2^2)/2 (g is accelerating downwards, so negative)
= 1.593 m
The net displacement after 2 seconds is
D = <Dx,Dy> = <42.426, 1.593> m to three decimal places
