Final answer:
In Piaget's sensorimotor stage, children make two notable errors: object permanence and conservation.
Step-by-step explanation:
In Piaget's sensorimotor stage of cognitive development, two notable errors that children make are:
- Object Permanence: Prior to developing object permanence, young infants do not remember an object after it has been removed from sight. Piaget studied infants' reactions to a hidden toy and found that infants who had not developed object permanence appeared confused.
- Conservation: Young children in the sensorimotor stage have not yet developed an understanding of conservation, which is the idea that even if you change the appearance of something, it is still equal in size as long as nothing has been removed or added. For example, a child may believe that a taller glass contains more liquid than a shorter glass, even if the amount is the same.