A concave mirror is used in a solar cooker. Specifically, a concave mirror focuses sunlight onto a small area, increasing the intensity of the sunlight and generating heat. This concentrated sunlight is then used for cooking in solar cookers, harnessing solar energy for practical applications.

The refractive index of diamond is approximately 2.42. Diamond has a very high refractive index, which means it bends light at a significant angle when it enters the diamond, contributing to its sparkling brilliance.

The Richter magnitude scale (often shortened to Richter scale) was developed to assign a single number to quantify the energy that is released during an earthquake. An earthquake (also known as a quake, tremor or temblor) is the result of a sudden release of energy in the Earth’s crust that creates seismic waves.

the edible part of a coconut is the endosperm. The endosperm is the inner, white, and fleshy part of the coconut seed, which is commonly consumed as food. It is often grated, dried, and used in various culinary applications or processed to extract coconut milk and oil. Coconut water, found inside young green coconuts, is also consumed as a refreshing beverage and is distinct from the endosperm.