Department of Pre-University Education, KarnatakaPUC Karnataka Science Class 11

# Consider the Equations P = Lim △ S → 0 F △ S and P1 - P2 = Pgz. in an Elevator Accelerating Upward - Physics

MCQ

Consider the equations P=lim_(triangles->0)"F"/(triangle"S") and P1 - P2 = pgz. In an elevator accelerating upward

#### Options

• both the equations are valid

• the first is valid but not the second

• the second is valid but not the first

• both are invalid

#### Solution

the first is valid but not the second
For a point inside the elevator, pressure can be defined as P=lim_(triangles->0)"F"/(triangle"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 P1 - P2 = ρ(g+a0)z

Here, acceleration a0 (say) due to elevator accelerating upwards is also taken into account.

Is there an error in this question or solution?

#### APPEARS IN

HC Verma Class 11, 12 Concepts of Physics 1
Chapter 13 Fluid Mechanics
MCQ | Q 2 | Page 271