Question

after winters people pack of the Woodlands bike keeping naphthalene ball in them with passage of time these boys became smaller in size why does this happen what type of changes involved during this process

Answer 1

NAPHTHALENE BALL UNDERGOES SUBLIMATION(PROCESS IN WHICH SOLID SUBSTANCE CHANGES ITS PHASE TO GAS WITHOUT PASSING THROUGH LIQUID PHASE).Unlike ice(water) where it first gets converted to liquid ,later to gas/vapour. 
Since naphthalene balls(solid) slowly undergo sublimation at room temperature,it is directly converted to gaseous state,leaving behind neither liquid nor solid trace.