# Question #51c44

Jan 26, 2017

$4.17 \times {10}^{5} N$, rounded to two decimal places

#### Explanation:

We know that

1. Absolute Pressure by definition is is zero-referenced against perfect vacuum.

2. Gauge Pressure is zero-referenced against ambient atmospheric pressure.

Therefore, Absolute Pressure is equal to gauge pressure $+$ atmospheric pressure.

In the given problem we have

Absolute pressure and Gauge pressure is $104 a t m \mathmr{and} 103 a t m$ respectively.
As such outside pressure acting on the window of submarine while at a depth of $1000 m = 104 a t m$
Inside pressure is maintained at sea level pressure$= 1 a t m$
Net inward pressure acting on the window$= 104 - 1 = 103 a t m$

We know that Pressure of $1 a t m = 101325 N {m}^{-} 2$
Also Pressure$= \text{Force"/"Area}$

$\therefore$Force acting on the window$= \text{Pressure"xx"Area of window}$
Inserting above values we get
Force acting on the window$= 103 \times 101325 \times \left(0.2 \times 0.2\right)$
$= 4.17 \times {10}^{5} N$, rounded to two decimal places