Physics
posted by Liz .
In projectile motion, how would you find the final velocity of the object just before it hits the ground
a) find the second vertical velocity
b) add the final and horizontal velocities directly
c)add the final and horizontal velocities as vectors
d) add the final and horizontal velocities as vectors and then determine the direction using trigonometry

You add the final VERTICAL velocity and the constant horizontal velocity as vectors. You can find the direction with trig if you wish, but the vector components imply direction as well as magnitude. For example
V = u i + v j
where u is the horizontal velocity component
v is the vertical velocity component
i is the unit vector in the x (horizontal) direction
j is the unit vector up