Physics

A rectifier is an electrical device that converts alternating current (AC), which periodically reverses direction, to direct current (DC), which flows in only one direction. The process is known as rectification, since it “straightens” the direction of current.

Based on the thermoelectric effect, the thermopile can be used as a heat sensor to measure thermal radiation. A thermopile is made of thermocouple junction pairs connected electrically in series. Thermocouples near the ground measures radiant energy.

A permanent magnet can affect both magnets and electromagnets.

Archimedes’ upward thrust will be absent for a fluid, if there were no gravity.

Silver has the maximum thermal conductivity.

Glass wool is best used as a sound absorbing material in partition walls. This is so because glass wool do not transfer mechanical energy. These tend to be soft, flexible, low density, and with high surface area to linear area ratios.