What things use pressure to work?

Answer 1

1) hydraulic elevator:

Hydraulic elevator systems lift a car using a hydraulic ram, a fluid-driven piston mounted inside a cylinder. You can see how this system works in the diagram below.

The cylinder is connected to a fluid-pumping system(typically, hydraulic systems like this use oil, but other incompressible fluids would also work). The hydraulic system has three parts:

• A tank (the fluid reservoir)
• A pump, powered by an electric motor
• A valve between the cylinder and the reservoir

The pump forces fluid from the tank into a pipe leading to the cylinder. When the valve is opened, the pressurized fluid will take the path of least resistance and return to the fluid reservoir. But when the valve is closed, the pressurized fluid has nowhere to go except into the cylinder. As the fluid collects in the cylinder, it pushes the piston up, lifting the elevator car.

When the car approaches the correct floor, the control system sends a signal to the electric motor to gradually shut off the pump. With the pump off, there is no more fluid flowing into the cylinder, but the fluid that is already in the cylinder cannot escape (it can't flow backward through the pump, and the valve is still closed). The piston rests on the fluid, and the car stays where it is.

2) using ice skates instead of normal shoes: the shoe distributes the force over a much larger area than the skates does. this means that the skates exerts a much higher pressure on the ice than the shoe does- this high pressure makes ice skating possible.

Answer 2

1) mouth organ

2) pressure cooker

3)cycle pump etc. are some examples that work on air pressure.