PROGRAM Projectile
!---------------------------------------------------------------------
! This program calculates the velocity and height of a projectile
! given its initial height, initial velocity, and constant
! acceleration. Identifiers used are:

!   InitialHeight   : initial height of projectile (meters)
!   Height          : height at any time (meters)
!   InitialVelocity : initial vertical velocity (m/sec)
!   Velocity        : vertical velocity at any time (m/sec)
!   Acceleration    : vertical acceleration (m/sec/sec)
!   Time            : time since launch (seconds)
!
! Input:  InitialHeight, InitialVelocity, Time
! Output: Velocity, Height
!---------------------------------------------------------------------

  IMPLICIT NONE
  REAL :: InitialHeight, Height, InitialVelocity, Velocity,  &
          Acceleration = -9.80665,  &
          Time

  ! Obtain values for InitialHeight, InitialVeloc, and Time
  PRINT *, "Enter the initial height (m) and velocity (m/sec):"
  READ *, InitialHeight, InitialVelocity
  PRINT *, "Enter time in seconds at which to calculate height and velocity:"
  READ *, Time

  ! Calculate the height and velocity
  Height = 0.5 * Acceleration * Time ** 2  &
           + InitialVelocity* Time + InitialHeight
  Velocity = Acceleration * Time + InitialVelocity

  ! Display Velocity and Height
  PRINT *, "At time", Time, "seconds"
  PRINT *, "the vertical velocity is", Velocity, "m/sec"
  PRINT *, "and the height is", Height, "meters"

END PROGRAM Projectile