Physics

Copper is the best conductor of heat.

The color of a star mostly indicates a star’s temperature, and it can also suggest the star’s age. Class O stars, which are blue in color, are the hottest, and class M stars, which are red in color, are the coldest.

At high altitude pressure is low and therefore the boiling point is also low. In this case, water starts boiling below its boiling point but rice cooks at 100. So, it is difficult to cook rice at high altitudes.

Soft iron provides the best material for the core of a transformer as its permeability (μ) is very high. Its hysteresis curve is of small area and its coercivity is very low.

A microscope is an instrument that produces a clear magnified image of an object viewed through it. A basic microscope is made up of two converging lenses. The first lens creates a real image which serves as the object for the second lens, and the image created by the second lens is the one a viewer sees. The final image is virtual and is inverted compared to the original object.