Moving an image WinForms VS WPF

Question

Hi, im currently converting one of my projects from winforms to wpf.
i had this line of code in winforms (greenCar is picturebox control):
int speed = 5

            greenCar.Top = greenCar.Top + speed;

basically im trying to move the picture downwards in each tick of the timer which this function running in.

what code line is doing the same thing in WPF application?
thanks in advance :)