I recently noticed a fad or fashion (probably over now) for animated curves as a secondary animation to engage attention, but not distract, from the main text/image. This tutorial video for AE revisits a very old way of creating such effects.
Then without the Green box the Blue box would receive and emit 150J/sec and working back from S.B, emitted E=T^4, has a temp of ~ 196KWith the Green box returning and extra 10J/sec to the Blue box as back radiation it emits 160J/sec and has a temp of 200K.
The Green box receiving and emitting 40J/sec has a temp of ~141K
For the context and further explanation please see the full post.