Physics Quiz 4

A rectifier is a special type of diode that converts alternating current (AC) into direct current (DC).

All objects, regardless of mass, will fall at the same rate. Heavier things have a greater gravitational force AND heavier things have a lower acceleration. It turns out that these two effects exactly cancel to make falling objects have the same acceleration regardless of mass.

An electron microscope is a microscope that uses a beam of accelerated electrons as a source of illumination. It was invented by Ernst Ruska (physicist) and Max Knoll (electrical engineer), from the University of Berlin in 1931.

Lambert's law is related to Illumination. This law stated that the loss of light intensity when it propagates in a medium is directly proportional to intensity and path length.

From this, we can estimate the radius of the earth as the point of the horizon must cover the circumference of the Earth.

Water and petrol are immiscible with each other and petrol which forms the upper layer continues to burn. Water is heavier than petrol, petrol will come above the water and continue the contact with the atmosphere (oxygen).

Surface tension is the tendency of liquid surfaces at rest to shrink into the minimum surface area possible. The hair of a shaving brush clings together when removed from water due to Surface tension.

Alnico is a family of iron alloys which in addition to iron are composed primarily of aluminium (Al), nickel (Ni), and cobalt (Co), hence the acronym al-ni-co. They also include copper, and sometimes titanium. Alnico alloys are ferromagnetic, and are used to make permanent magnets.

Steam produces more severe burns than boiling water. Steam at 100°C has more heat than water at the same temperature. Water gets converted into steam on gaining heat. Due to this latent heat of vaporisation, steam at 100°C is better for heating than boiling water at 100°C.

A sling psychrometer can be used to find relative humidity, which is expressed as a percentage.