Volumetric efficiency in internal combustion engine engineering is defined as the ratio of the mass density of the air-fuel mixture drawn into the cylinder at atmospheric pressure to the mass density of the same volume of air in the intake manifold.

A voltmeter is an instrument used for measuring electric potential difference between two points in an electric circuit.

The voltaic pile was the first electrical battery that could continuously provide an electric current to a circuit.

VSC HVDC systems use insulated-gate bipolar transistors to provide switching ability of the IGBTs to on and off many times per cycle in order to improve the harmonic performance and removing the requirement for synchronous machines in the AC system for its operation.

A voltage source is a two-terminal device which can maintain a fixed voltage.

A voltage regulator is a system designed to automatically maintain a constant voltage.

n electrical engineering, particularly power engineering, voltage regulation is a measure of change in the voltage magnitude between the sending and receiving end of a component, such as a transmission or distribution line.

Voltage drop is the decrease of electrical potential along the path of a current flowing in an electrical circuit.

A voltage controller, also called an AC voltage controller or AC regulator is an electronic module based on either thyristors, TRIACs, SCRs or IGBTs, which converts a fixed voltage, fixed frequency alternating current (AC) electrical input supply to obtain variable voltage in output delivered to a resistive load.

Voltage is defined as the difference of electric potentials between points in an electric field.

In chemistry, volatility is a material quality which describes how readily a substance vapourises.

Volatile organic compounds are organic chemicals that have a high vapour pressure at room temperature.

Volatility is measured by the day-to-day difference in the price of electricity.

Vojens is known to be the solar city number one. The world largest solar heating plant (70,000 m2) and the world largest underground thermal storage pit (200,000 m3).

The void coefficient is a number that can be used to estimate how much the reactivity of a nuclear reactor changes as voids (typically steam bubbles) form in the reactor moderator or coolant.

Vitrification is the transformation of a substance into a glass, an important application is the vitrification of radioactive waste to obtain a substance that is hopefully safer and more stable for disposal.

The impairment of the ability to enjoy a pleasant view as in high concentrations of electricity power lines.

Visual Inspection, used in maintenance of facilities, mean inspection of equipment and structures using either or all of raw human senses such as vision, hearing, touch and smell and/or any non-specialized inspection equipment.

The viscosity of a fluid is a measure of its resistance to deformation at a given rate.

A visbreaker is a processing unit in an oil refinery whose purpose is to reduce the quantity of residual oil produced in the distillation of crude oil and to increase the yield of more valuable middle distillates (heating oil and diesel) by the refinery.