Convex and concave lens

A plastic beaker is a laboratory container made from plastic material, typically featuring a cylindrical shape with a flat bottom and a spout or pouring lip. It is used for holding, measuring, and mixing liquids or substances during various scientific experiments, research, or educational activities. Plastic beakers come in a range of sizes and are designed to withstand various chemicals and temperatures, making them versatile tools in laboratory settings.

The Bernoulli tube apparatus, also known as a Venturi tube apparatus, is a scientific device used to demonstrate the principles of fluid dynamics, particularly the Bernoulli's principle. It consists of a specially shaped tube with a constricted region, often referred to as a Venturi section. When fluid (liquid or gas) flows through the tube, the constricted section leads to changes in pressure and velocity according to Bernoulli's principle, which states that as the velocity of a fluid increases, its pressure decreases and vice versa. This apparatus is commonly used in educational settings to visually illustrate how the flow of a fluid can affect its pressure, helping to explain various phenomena like lift in aircraft wings, fluid flow through pipes, and more.