What is meant by 'cognitive validity' in a science curriculum?

In a Physics class, a teacher wants to explain the concept of a closed electric circuit. She refers to the human circulatory system, comparing the heart to a battery and the flow of blood through vessels to the flow of electric current through a circuit. Which pedagogical device is the teacher primarily using in this explanation?

A teacher assigns a task to her Class VIII students: 'Interview 10 children from your neighbourhood to find out their food habits and diet. On the basis of information collected, identify the healthy diet patterns among the children.' Students are expected to interact with peers, record responses systematically, and draw conclusions about nutritional patterns. Which process skills are primarily being promoted through this activity?