(11%) Problem 5: A submarine is stranded on the bottom of the ocean with its hatch 25 m below the surface. In this problem, assume the density of sea water is 1.03 × 103 kg/m3. show answer No Attempt Calculate the force, in newtons, needed to open the hatch from the inside, given it is circular and 0.25 m in diameter. The air pressure inside the submarine is 1.00 atm.

12387N

Explanation:

1 atm = 101325 Pa

Let g = 9.8 m/s2. The pressure of the sea water at 25 m below the surface is:

So the pressure difference between inside the submarine and outside is

The area of the hatch which is subjected to this pressure is:

So the force required to win over the pressure difference is:

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weight of the box is given as

here this is placed on the inclined of angle 42 degree

now this weight will have two components one is along the incline other is perpendicular to it

so here we need to apply a force parallel to incline opposite to its component of weight

so here the component of weight is given as

here we have

so it requires 75 n force to move it upwards