21i guess u'll also hav 2 use da fact that the tube is at a depth of 12cm [12] [7]
the lower end of capillary tube is at a depth of 12 cm in water and the water rises 3 cm in it The mouth pressure required to blow an air bubble at the lower end will be
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11 Answers
24Guess........[3]
To blow bubble ,Presusre force applied=Excess Pressure Force
=> (Patm+Ïgh)A=(2T/r) A...............
forgive me if i am wrong here........[1]
2124why extra pressure dear???????????????we have to blow it not burst it.......there has to be equilibrium condition.........[12]
3no yaar any bubble will hav more pressure than its surroundings!!!!!!!!!!!!!!!
if u oberve the crossection of the BUBBLE...................
2Ï€RT will hold it together and excess pressure(P)Ï€R^2 WILL TRY AND SEPERATE IT ONLY IF U HAV SUM EXCESS PRESSURE WILL THE BUBBLE STAY ELSE IT WILL COLLAPSE!!!
24tell the ans karan.............then we will search for flaws....[1]
1the correct ans is (d)
the options given in the ques are
a)3 cm of water column
b)9 cm of water column
c)12 cm of water column
d)15 cm of water column