When the opening is small, the blue square seems to be getting bigger and smaller. Thus, this illusion is called ‘Breathing Square’ illusion. As you can see below when the opening get bigger, what’s inside is just a rotating square, which doesn’t get bigger or smaller.
Use Turtle’s timer events to draw a simple timer as shown. Related Project: Millisecond Timer
Generate 50 random numbers and draw them as bars. Following the steps of insertion sort algorithm and redraw the bar every single step to show how bubble sort works. Compare
Continue from previous rolling triangle animation. Let it roll three times on the ground.
