The second one is called Science on Tap.

VOA: special.2010.05.14

If you tap somebody on the knee, your leg will jump out.

如果你轻击某人的膝盖,小腿就会弹出去

耶鲁公开课 - 心理学导论课程节选

She uses both hands to finger-tap on the flat narrow part of the guitar called the fretboard.

VOA: special.2011.01.28