Question

Sometimes it is hard to open the kettle after putting boil water or tea in it :
a. Because of its high temperature
b. Because of change in its dimension due to temperature rise
c. Because of its manufacturing defects
d. Because of low strength of person opening it

Answer 1

$\red{Option\:b\:is\:correct}$

Since temperature get increase the molecules of body of kettles expand and slightly change in shape this results in tightness of cap of kettle.

Hence it become tough to open it.