No its c
@Chirag_Hegde Is right. It's B.
How??answer is c
∆P=4T/R, and R is increasing with time, so only B matches this.
@Viraam_Rao please confirm bro
Getting B. I think the answer key is wrong.
"Supplying air at constant rate" That means number of moles of gas in bubble is increasing at constant rate right?
I took it as volume of air.
But volume changes with pressure, so it doesn't make proper sense saying you're adding a particular volume of air per second inside.
Answer says that it initially increases and becomes constant after sometime but no explanation is given @Chirag_Hegde
If that's the case we must be getting some exponential function......
Can you elaborate? I didn't get you.
Did you consider that volume of bubble is increasing at constant rate?
Yeah. I thought that's what the question meant by constant rate.
I don't think so. I think it's number of moles.
Excess pressure doesn't depend on number of moles right? Just the radius
Yes, and radius depends on number of moles.
Even if they meant no of moles per unit time, the bubble's radius has to increase with time.
So the above will still apply right
That's right even I'm getting B. But I don't think FIITJEE can be wrong. (Can it be @Chirag_Hegde ?) Kuchh to pakad me nahi aa raha hai.