Pressure in Fluids — Prelims Questions

A hydraulic lift is designed to lift cars. The area of the input piston is $0.05,\text{m}^2$, and the area of the output piston is $1.5,\text{m}^2$. If a force of $200,\text{N}$ is applied to the input piston, what is the maximum weight (in Newtons) that can be lifted by the output piston?

A diver is at a depth of $20,\text{m}$ in seawater. If the density of seawater is $1025,\text{kg/m}^3$ and atmospheric pressure is $1.01 \times 10^5,\text{Pa}$, what is the absolute pressure experienced by the diver? (Take $g = 9.8,\text{m/s}^2$)

Which of the following statements about pressure in a static fluid is INCORRECT?

A U-tube manometer contains mercury (density $13600,\text{kg/m}^3$). One arm is open to the atmosphere, and the other is connected to a gas tank. If the mercury level in the arm connected to the gas tank is $15,\text{cm}$ lower than the level in the open arm, what is the gauge pressure of the gas in the tank? (Take $g = 9.8,\text{m/s}^2$)

An open tank contains water up to a height of $5,\text{m}$. An oil layer of $2,\text{m}$ thickness floats on top of the water. If the density of oil is $800,\text{kg/m}^3$ and the density of water is $1000,\text{kg/m}^3$, what is the absolute pressure at the bottom of the tank? (Take atmospheric pressure $P_{atm} = 1.01 \times 10^5,\text{Pa}$ and $g = 10,\text{m/s}^2$)

Two points A and B are at the same horizontal level within a continuous static fluid. Which of the following statements is true regarding the pressure at these points?