NEET-XII-Physics
13: Fluid Mechanics
- #2Consider the equations
P=lim∆s→0F∆S and P1-P2=ρgz.In an elevator accelerating upward
(a) both the equations are valid
(b) the first is valid but not the second
(c) the second is valid but not the first
(d) both are invaliddigAnsr: bAns : (b) the first is valid but not the second
For a point inside the elevator, pressure can be defined as `` P=\underset{∆s\to 0}{\,\mathrm{\,lim\,}}\frac{F}{∆S}``. It is independent of the acceleration of the elevator.
The modified form of the second equation, which will be valid in the given case, is given by
`` {P}_{1}-{P}_{2}=\rho (g+{a}_{0})z``
`` ``
Here, acceleration a0 (say) due to elevator accelerating upwards is also taken into account.`` ``
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