Hi! need help please thank you so much.

Question:(a) Calculate the absolute pressure at the bottom of a freshwater lake at a depth of 28.7 m. Assume the density of the water is 1.00 103 kg/m3 and the air above is at a pressure of 101.3 kPa.
___Pa

(b) What force is exerted by the water on the window of an underwater vehicle at this depth if the window is circular and has a diameter of 40.9 cm?
___ N

Pressure at bottom = pressure at surface + rho g h

= 1.013 *10^5 Pa + 10^3 * 9.81* 28.7

= 1.013 * 10^5 + 2.815 * 10^5

= 3.83 * 10^5 Pascals

To calculate the absolute pressure at the bottom of the freshwater lake, you can use the formula for hydrostatic pressure:

P = P0 + ρgh

where P is the absolute pressure at the bottom, P0 is the atmospheric pressure (101.3 kPa), ρ is the density of the water (1.00 × 10^3 kg/m^3), g is the acceleration due to gravity (9.8 m/s^2), and h is the depth (28.7 m).

(a) Calculating the absolute pressure:

P = 101.3 kPa + (1.00 × 10^3 kg/m^3) × (9.8 m/s^2) × (28.7 m)

You can convert the kilopascals to pascals by multiplying by 1000:

P = (101.3 × 10^3 Pa) + (1.00 × 10^3 kg/m^3) × (9.8 m/s^2) × (28.7 m)

Evaluating this expression will give you the answer in pascals.

(b) To calculate the force exerted by the water on the window of the underwater vehicle, you can use the formula:

F = P × A

where F is the force, P is the pressure (which we just calculated), and A is the area of the circular window.

To find the area of the circular window, you can use the formula:

A = πr^2

where r is the radius of the window (half of the diameter). Given that the diameter is 40.9 cm, you can convert it to meters (by dividing by 100) and then find the radius.

Once you have the pressure and the area, you can calculate the force.

I hope this explanation helps you!