4-2.scm

; Calc a distance of a thrown object
(define pi (* 4 (atan 1.0))) ; pi = 4atan(-1)
(define gravaccr 9.8) ; gravitial accelaration

(define CalcDistance
  (lambda (v0 deg) 
    (define DegreeToRadian
      (lambda (degree)
  (/ (* degree pi) 180)))
    (define CalcDistanceX
      (lambda (vx t)
	(* vx t)))
    (define CalcTimeY
      (lambda (vy)
	(/ (* 2 vy) gravaccr )))
    (define t 
      (CalcTimeY (* v0 (sin (DegreeToRadian deg)))))
    (* (CalcDistanceX (* v0 (cos (DegreeToRadian deg))) t))))

(display (CalcDistance 40 30)) ; display the result
(display "\n")