Question

Frank has been asked to complete piaget's pendulum problem. he comes up with some hypotheses and then systematically tests each variable. first, he holds the length of the string and the amount of weight constant and varies the height at which oscillation is started then he moves on to examining the other variables. frank is in which stage of piaget's cognitive developmental theory?

Answer 1

I believe the answer is: Formal operation

Piaget's formal operation refers to the stage of development when people started to develop the ability to understand abstract concept and started to manipulate ideas in their head.
This stage usually reached by the age of 12- adulthood.