EXPLANATION
- a) Newton
- b) Joule
- c) Pascal
- d) Kilogram
ANSWER: c) Pascal
EXPLANATION:
The unit of pressure in the SI (International System of Units) system is the Pascal (symbol: Pa). Pascal is named after the French mathematician and physicist Blaise Pascal and is defined as one Newton per square meter (N/m²). It is a derived unit in the SI system, representing the amount of force exerted per unit area. Pressure is often measured in kilopascals (kPa) or megapascals (MPa), which are multiples of the Pascal. The Pascal is widely used in scientific, engineering, and everyday contexts for measuring pressure.
Pressure is a physical quantity that measures the force applied to a surface per unit area. It quantifies how much force is distributed over a given area. Pressure is a fundamental concept in physics and finds applications in various fields such as fluid dynamics, engineering, and meteorology.
Mathematically, pressure (P) is defined as the ratio of the force (F) applied perpendicular to a surface to the area (A) over which the force is distributed:
P = F / A
In the SI system, pressure is measured in Pascal (Pa), as mentioned earlier. One Pascal is equal to one Newton per square meter (N/m²).
Pressure can be exerted by various means, such as solids, liquids, and gases. For example, when a person stands on the ground, their weight is distributed over the contact area with the ground, resulting in pressure. Similarly, when a gas is confined to a container, the gas molecules exert pressure on the walls of the container due to their collisions with the walls.
Pressure can have different effects depending on the context. In fluids, it plays a role in determining the flow of liquids and gases. For example, pressure differences drive fluid flow through pipes or cause winds in the atmosphere. In solids, pressure can cause deformation or structural changes.
It's important to note that pressure is a scalar quantity, meaning it has magnitude but no specific direction. However, pressure gradients can exist, indicating how pressure changes over a particular direction or spatial region. These gradients often contribute to various phenomena and processes, such as fluid flow or atmospheric dynamics.
