Question

Why do bigger air bubbles rise faster than the smaller ones in boiling water

Answer 1

Just because Archimedes principle is valid .....
the more the volume anything takes the more force acts on it , that's it
Archimedes principle says that the amnt of force acting on a body inside a fluid is equal to the weight of the fluid it have displaced
bigger bubble displace more water so more force acts on them and the mass is negligible , so they rise faster
Hope it helps , have a great day !

Answer 2

 Best Answer

It has to do with bouyancy and drag much like a kilo of loose gravel will fall through the air faster than a kilo of loose feathers. Both of them have the same force of gravity working to pull them to the earth, the feathers just have a larger surface area to drag through the resisting air. The ratio of surface drag to pull is greater for the feathers than for the gravel 

small bubbles have a larger surface area in relation to their volume than large bubbles do. 
Drag is proportional to the surface area 
If you model bubbles as perfect spheres (they aren't, of course, but the general affect is the same) 
the surface area of a sphere increases as the square of the radius 
A = 4πr² 

yet the volume of a sphere increases as the cube of the radius 
V = 4πr³/3 

so a larger bubble displaces more water per square area. 
As the lifting force on the bubble is proportionate to the volume of water displaced, the ratio of lifting force to retarding drag is greater for the larger bubble than for the small. The big bubble rises faster.
OR
THIS ONE
Bubbles in liquid are essentially air pockets and air is less dense than water. So therefore the bigger bubble contains more air so will rise alot quicker. It's the same as if u fill two different balloons with different amounts of helium, the one with more helium will rise quicker....
HOPE IT HELPS.......!!!!!