G.K. (General Science) - 3

A tachometer is a device used to measure the rotation speed of a shaft or disk, such as in a motor or engine. Pyrometers measure temperature, anemometers measure wind speed, and dynamometers measure force or torque.

The Sun is the primary source of energy for Earth, providing light and heat that drive weather patterns, photosynthesis, and most biological processes. The atmosphere and oceans are mediums for energy distribution rather than primary sources.

Acoustic radar, also known as SODAR (Sonic Detection and Ranging), relies on the reflection of sound waves. Sound waves are a type of elastic wave that requires a medium to propagate.

A light year is the distance light travels in one year, which is the standard unit for measuring vast astronomical distances between stars. Microns and Angstroms are used for microscopic or atomic scales.

 mho or siemens are the units of conductance

Weight is the force exerted by gravity on an object. At the center of the Earth, the gravitational pull from all directions cancels out, resulting in zero weight.

Albert Einstein is famous for his theory of relativity, which fundamentally changed our understanding of space, time, and gravity. Gravitation was described by Newton, X-rays by Roentgen, and radioactivity by Becquerel.

In outer space, there is no atmosphere to scatter sunlight, which is why the sky does not appear blue as it does on Earth. Consequently, the lack of scattered light makes space appear black.

Rockets operate based on Newton's third law of motion, which is a direct application of the law of conservation of momentum. Expelling gas at high speed in one direction creates an equal and opposite force that propels the rocket forward.

J.J. Thomson discovered the electron in 1897 through his experiments with cathode ray tubes. James Chadwick discovered the neutron, and Ernest Rutherford is known for the proton and the atomic nucleus.

The Newton is the SI unit of force, including electric force. The Coulomb is the unit of electric charge, and the Farad is the unit of electric capacitance.

The Farad is the SI unit of electrical capacitance. A capacitor's ability to store charge is measured in Farads.

The Angstrom is a unit of length equal to 10^-10 meters, commonly used to express the size of atoms and inter-atomic distances in solids. Microns are larger, and light years are for astronomical distances.

Wilhelm Conrad Roentgen discovered X-rays in 1895. Gravitation is attributed to Newton, relativity to Einstein, and radioactivity to Becquerel.

Electron microscopes utilize the wave-like properties of electrons, which are described as matter waves (de Broglie waves). This allows for much higher resolution than optical microscopes.

The Coulomb is the SI unit of electric charge. It represents the amount of charge transported by a constant current of one ampere in one second.

An anemometer is an instrument used to measure the speed or velocity of a fluid, typically air or wind. Pyrometers measure temperature, and tachometers measure rotational speed.

Isaac Newton formulated the law of universal gravitation in his work Principia. Relativity is Einstein's work, X-rays are Roentgen's, and radioactivity is Becquerel's.

Henri Becquerel discovered radioactivity in 1896 while investigating uranium salts. Gravitation is Newton's, relativity is Einstein's, and X-rays are Roentgen's.

The core of a transformer is made of soft iron to provide a low-reluctance path for the magnetic flux, which increases the efficiency of the magnetic coupling between the primary and secondary coils.

Musical instruments produce sound, which travels through the air as longitudinal waves. These waves consist of compressions and rarefactions of the medium.

A pyrometer is a type of remote-sensing thermometer used to measure the temperature of surfaces, particularly high temperatures where contact thermometers would be damaged.

A dynamometer is a device for measuring force, torque, or power. It is commonly used to measure the power output of engines or motors.

The wavelength of infrared laser light is typically in the micrometer (micron) range. Angstroms are too small for infrared, and light years are far too large.

Lasers produce electromagnetic radiation (light). In surgical applications, the electromagnetic waves are focused to cut or cauterize tissue.