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A circular window 30 cm in diameter in a submarine can withstand a maximum force, exerted by the fluids surrounding it, of 5.20 × 105 N without damage. What is the maximum depth in a fresh-water lake to which the submarine, containing air at atmospheric pressure, can go without damaging the window? The density of fresh water is 1000 kg/m3.

User Xelurg
by
5.2k points

2 Answers

4 votes

Final answer:

The maximum depth the submarine can go without damaging the window is approximately 5.59 meters.

Step-by-step explanation:

To determine the maximum depth the submarine can go without damaging the window, we need to consider the pressure exerted by the water at that depth. The pressure at a certain depth in a fluid can be calculated using the formula:

Pressure = density × gravity × height

Given that the diameter of the window is 30 cm, we can calculate its radius (r) as 15 cm or 0.15 m. The area of the window (A) can be calculated using the formula for the area of a circle (A = πr^2). Since the force the window can withstand is mentioned, we can assume that the maximum pressure it can withstand is reached at its weakest point, which is at the center. Using the equation for pressure, we can solve for the maximum depth (h) as follows:

Pressure = Force / Area

Force = 5.20 × 105 N

Area = π × (0.15 m)^2

Pressure = 5.20 × 105 N / (π × 0.15 m^2)

Solving for the maximum depth:

Pressure = density × gravity × height

5.20 × 105 N / (π × 0.15 m^2) = 1000 kg/m^3 × 9.8 m/s^2 × height

height = (5.20 × 105 N / (π × 0.15 m^2)) / (1000 kg/m^3 × 9.8 m/s^2)

height ≈ 5.59 m

User Negus
by
5.4k points
5 votes

Answer:

755 m

Step-by-step explanation:

Given:

Diameter of the window, d = 30 cm

= 0.3 m

Therefore, radius r = 0.15 m

Force, F =
5.2* 10^(5)N

Density, ρ = 1000kg/m3

Thus, Area of the window, A =
\pi * r^(2)

=
3.14 * 0.15^(2)

= 0.07
m^(2)

Therefore pressure, P = Force / Area

=
5.2* 10^(5)N / 0.07

=
7.4 * 10^(6)

We know that, pressure, P = ρ.g.h

where, g is acceleration due to gravity =
9.8 m/s^(2)

h is depth

Therefore, P = ρ.g.h

or h =
(P)/(\rho * g)

=
(7.4* 10^(6))/(1000* 9.8)

= 755 m

Thus the maximum depth is 755 meter.

User Rasmus Kaj
by
5.3k points