A 30m high cylindrical water tank has a diameter of 14m. The tank is two-thirds full of water. What is the pressure at the bottom of the tank?

diameter does not matter

p = density * g * depth

(the weight of water in a 1 m^2 column)
so
water weighs 1000 kg/m*3
so we are talking a mass of 1000 * 20

20,000 * 9.81 = 196,200 or 1.96*10^5 Newtons/m^2 or Pascals
HOWEVER on to of that you have the air pressure which is about 10^5 Pascals
so for total pressure about 2.96*10^5 Pascals

To find the pressure at the bottom of the water tank, we can use the formula:

Pressure = Density * Gravitational Acceleration * Height

First, let's find the height of the water in the tank. We know that the tank is two-thirds full, so we can calculate:

Height of water = two-thirds * Height of the tank
= (2/3) * 30m
= 20m

The density of water is approximately 1000 kg/m^3, and the gravitational acceleration is approximately 9.8 m/s^2.

Using these values, we can calculate the pressure:

Pressure = 1000 kg/m^3 * 9.8 m/s^2 * 20m
= 196,000 Pascal

Therefore, the pressure at the bottom of the tank is 196,000 Pascal.