Which of the following is/are both physical and reversible changes?
Inflating a balloon
Conversion of paper to a paper boat
Physical change:- In a physical change no new substance is formed and the chemical composition of substance remains the same. There are changes in physical properties like shape, size, etc.
Reversible change:- A process in which the original form of substance can be retained by any physical process is known as reversible change. These changes are temporary changes.
Inflating a balloon, conversion of paper to a paper boat - both are physical and reversible changes because no new substance is formed and the original state of substances can be reattained. By removing air from the inflated balloon can reattain the original shape of the balloon and unfolding paper boat can reattain the original shape of the paper.
Pricking an inflated balloon, tearing of paper - both are physical and irreversible changes because in these changes the original state of the substance cannot be reattained.