A rectangular tank is 2m long and 5m wide. It contains water to a depth of 6m. calculate:

a. the pressure at a depth of 3m
b. the total thrust in meganewtons on
(i) the bottom of the tank
(ii) one of the sides of the tank

To calculate the pressure at a given depth in a fluid, we can use the formula:

Pressure = density x gravitational acceleration x height

where:
- density is the density of the fluid (water in this case),
- gravitational acceleration is the acceleration due to gravity (approximately 9.8 m/s^2 on Earth),
- height is the depth at which we want to calculate the pressure.

a. For the pressure at a depth of 3m in the water tank:
- density of water is approximately 1000 kg/m^3
- gravitational acceleration (g) is 9.8 m/s^2

Using the formula, we can calculate the pressure at 3m depth:
Pressure = 1000 kg/m^3 x 9.8 m/s^2 x 3m

b. To calculate the total thrust on the bottom and one side of the tank, we need to determine the force exerted by the water.

i. Total thrust on the bottom of the tank:
The total thrust on the bottom of the tank is equal to the weight of the water above it. So, we need to calculate the weight of the water.

Weight = mass x gravitational acceleration

To calculate the mass of water on the bottom:
- length = 2m
- width = 5m
- depth = 6m
- density of water = 1000 kg/m^3

First, calculate the volume of water on the bottom:
Volume = length x width x depth

Then, calculate the mass of water on the bottom using the volume and density:
Mass = Volume x density

Finally, calculate the total thrust on the bottom:
Thrust = Mass x gravitational acceleration

Convert the thrust to meganewtons by dividing by 1,000,000.

ii. Total thrust on one side of the tank:
The total thrust on one side of the tank is equal to the weight of the water in that side. We can calculate it using the same process as in (i), but with different dimensions.

- length = 2m
- width = 6m (consider the longer side for simplicity)
- depth = 6m
- density of water = 1000 kg/m^3

First, calculate the volume of water on the side:
Volume = length x width x depth

Then, calculate the mass of water on the side using the volume and density:
Mass = Volume x density

Finally, calculate the total thrust on the side:
Thrust = Mass x gravitational acceleration

Convert the thrust to meganewtons by dividing by 1,000,000.

Now you have the complete process to calculate the pressure at a depth of 3m and the total thrust on the bottom and one side of the tank. You can plug in the values to get the final numerical results.