According to this video the length of basis
is r. It grows as we further from the origin . Why?
There is not really a "length" of it, but you can consider how far you move if you move by a small ##\epsilon \hat \theta##, the length increases with the radius.
Thanks. That makes sense. But why would the 'length' be r as Pavel Grinfeld says in the video.
Set ##\epsilon=1##. With 2 pi you get a length of 2 pi r, with 1 you would expect a length of r. Sort of.
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