It was Paheli’s birthday, her brother Simba was helping her to decorate the house for the birthday party and their parents were also busy making other arrangements. Following were
the activities going on at Paheli’s home: Identify the activities at Paheli’s home as those that can be reversed and those which cannot be reversed.
(i) Simba blew balloons and put them on the wall.
(ii) Some of the balloons burst.
(iii) Paheli cut colorful strips of paper and put them on the wall with the help of tape.
(iv) She also made some flowers by origami (paper folding) to decorate the house.
(v) Her father made dough balls.
(vi) Mother rolled the dough balls to make puris.
(vii) Mother heated oil in a pan.
(viii) Father fried the puris in hot oil.
the activities going on at Paheli’s home: Identify the activities at Paheli’s home as those that can be reversed and those which cannot be reversed.
(i) Simba blew balloons and put them on the wall.
(ii) Some of the balloons burst.
(iii) Paheli cut colorful strips of paper and put them on the wall with the help of tape.
(iv) She also made some flowers by origami (paper folding) to decorate the house.
(v) Her father made dough balls.
(vi) Mother rolled the dough balls to make puris.
(vii) Mother heated oil in a pan.
(viii) Father fried the puris in hot oil.
(i)
Blowing of a balloon can be reversed because the balloon filled with air during blowing and when the air is released from the balloon it attains its original state.
Hence, the given change is reversible.
(ii)
Bursting of balloons destroys the substance itself so the original form of the balloon cannot be recovered.
Hence, it is an irreversible change.
(iii)
Cutting colorful strips of paper decreases the size and shape of the paper and it cannot be fixed to get back its original form of the paper.
Hence, it is an irreversible change.
(iv)
Making flowers with the help of folding of paper to decorate the house can be reversed by unfolding the paper to get back its original form.
Hence, the given change is reversible.
(v)
Making a dough ball can be reversed by combining the dough balls to get back the dough.
Hence, the given change is reversible.
(vi)
Rolling dough ball to make puris is a reversible process because we can reshape the dough balls back to its original shape and form
Hence, the given change is reversible.
(vii)
Heating oil in a pan is a reversible process because the oil becomes hot on heating and cools down when there is no heat supply.
Hence, the given change is reversible.
(viii)
Once the puris are fried, they cannot be reversed because the dough gets cooked during the process of frying.
Hence, it is an irreversible change.
Blowing of a balloon can be reversed because the balloon filled with air during blowing and when the air is released from the balloon it attains its original state.
Hence, the given change is reversible.
(ii)
Bursting of balloons destroys the substance itself so the original form of the balloon cannot be recovered.
Hence, it is an irreversible change.
(iii)
Cutting colorful strips of paper decreases the size and shape of the paper and it cannot be fixed to get back its original form of the paper.
Hence, it is an irreversible change.
(iv)
Making flowers with the help of folding of paper to decorate the house can be reversed by unfolding the paper to get back its original form.
Hence, the given change is reversible.
(v)
Making a dough ball can be reversed by combining the dough balls to get back the dough.
Hence, the given change is reversible.
(vi)
Rolling dough ball to make puris is a reversible process because we can reshape the dough balls back to its original shape and form
Hence, the given change is reversible.
(vii)
Heating oil in a pan is a reversible process because the oil becomes hot on heating and cools down when there is no heat supply.
Hence, the given change is reversible.
(viii)
Once the puris are fried, they cannot be reversed because the dough gets cooked during the process of frying.
Hence, it is an irreversible change.
