Acceleration

Change in velocity over a certain amount of time.

Acceleration

The rate of increase of speed or the rate of change of velocity.

Ammeter

A device used to measure electric current in amps.

Ampere

The basic SI unit of electric current; the constant current that, when maintained in two parallel conductors of infinite length and negligible cross section placed 1 metre apart in free space, produces a force of 2 × 107 newton per metre between them. 1 ampere is equivalent to 1 coulomb per second.

Amplifier

An electronic device used to increase the strength of the signal fed into it.

Amplitude

The height or depth of the wave from the middle to the crest or trough respectively.

Amplitude

It is height of a wave, which is measured from its center position

Angle of Incidence

Angle between the normal and incident ray.

Angle of Reflection

Angle between the normal and reflected ray.

Atom

This entity as a source of nuclear energy.

Atomic mass unit

It is onetwelfth the mass of an atom of the isotope 12?6C.

Barometer

A device used to measure atmospheric pressure in Pascal.

Calorie

A unit of heat, equal to 4.1868 joules (International Table calorie): formerly defined as the quantity of heat required to raise the temperature of 1 gram of water by 1°C under standard conditions. It has now largely been replaced by the joule for scientific purposes.

Capacitance

The property of a system that enables it to store electric charge.

Charge

The attribute of matter by which it responds to electromagnetic forces responsible for all electrical phenomena, existing in two forms to which the signs negative and positive are arbitrarily assigned.

Condensation

The change of state from gas to liquid.

Condensed matter physics

A branch of physics that studies the physical properties of condensed phases of matter.

Conductor

A substance, body, or system that conducts electricity, heat, etc.

Convection

Transfer of energy in a liquid or gas due to different temperatures causing circulation within the fluid.

Convection

The process of transfer of heat by the actual transfer of matter.

Convection

The process by which masses of relatively warm air are raised into the atmosphere, often cooling and forming clouds, with compensatory downward movements of cooler air.

Current

A flow of electric charge through a conductor.

Density

The mass divided by the volume of an object.

Density

A measure of the compactness of a substance, expressed as its mass per unit volume. It is measured in kilograms per cubic metre or pounds per cubic foot

Earth

A connection between an electrical circuit or device and the earth, which is at zero potential.

Equilibrium

When two or more forces are balanced.

Evaporation

The change of state from liquid to gas.

Field

A region of space that is a vector field; a region of space under the influence of some scalar quantity, such as temperature.

Frequency

The number of waves passing through a point in a period of time.

Frequency

The number of times that a periodic function or vibration repeats itself in a specified time, often 1 second. It is usually measured in hertz.

Gravity

The force which pulls all objects within the earth's atmosphere towards the centre of the Earth.

Gravity

The force of attraction that moves or tends to move bodies towards the centre of a celestial body, such as the earth or moon.

Hertz

The derived SI unit of frequency; the frequency of a periodic phenomenon that has a periodic time of 1 second; 1 cycle per second.

Inductance

The property of an electric circuit as a result of which an electromotive force is created by a change of current in the same circuit (selfinductance) or in a neighbouring circuit (mutual inductance). It is usually measured in henries.

Joule

The derived SI unit of work or energy; the work done when the point of application of a force of 1 newton is displaced through a distance of 1 metre in the direction of the force. 1 joule is equivalent to 1 wattsecond, 107 ergs, 0.2390 calories, or 0.738 footpound.

Kelvin

The basic SI unit of thermodynamic temperature; the fraction 1?273.16 of the thermodynamic temperature of the triple point of water Symbol: K.

Kinematics

Geometry of motion.

Kinetic Energy

Motion energy. Any object that is moving is said to have kinetic energy.

Kinetic energy

The energy of motion of a body, equal to the work it would do if it were brought to rest. The translational kinetic energy depends on motion through space, and for a rigid body of constant mass is equal to the product of half the mass times the square of the speed. The rotational kinetic energy depends on rotation about an axis, and for a body of constant moment of inertia is equal to the product of half the moment of inertia times the square of the angular velocity. In relativistic physics kinetic energy is equal to the product of the increase of mass caused by motion times the square of the speed of light. The SI unit is the joule but the electronvolt is often used in atomic physics.

Longitudinal Waves

Waves in which the direction of the vibration is parallel to the direction in which the waves are moving.

Mass

The amount of matter in an object.

Mass

A physical quantity expressing the amount of matter in a body. It is a measure of a body's resistance to changes in velocity (inertial mass) and also of the force experienced in a gravitational field (gravitational mass): according to the theory of relativity, inertial and gravitational masses are equal.

Matter

Substance that occupies space and has mass, as distinguished from substance that is mental, spiritual, etc.

Melting

The change of state from a solid to a liquid.

Moment

A turning force. Calculated by multiplying the force and perpendicular distance from the pivot together.

Momentum

The product of a body's mass and its velocity.

Neutron

A neutral elementary particle with a rest mass of 1.674 92716 × 1027 kilogram and spin; classified as a baryon. In the nucleus of an atom it is stable, but when free it decays.

Newton

The derived SI unit of force that imparts an acceleration of 1 metre per second to a mass of 1 kilogram; equivalent to 105 dynes or 7.233 pounds.

Particle

A body with finite mass that can be treated as having negligible size, and internal structure.

Pascal

The derived SI unit of pressure; the pressure exerted on an area of 1 square metre by a force of 1 newton; equivalent to 10 dynes per square centimetre or 1.45 × 104 pound per square inch.

Pitch

The frequency of a sound wave. The higher the frequency the higher the pitch.

Planck constant or Planck's constant

A fundamental constant equal to the energy of any quantum of radiation divided by its frequency. It has a value of 6.62606876 × 1034 joule seconds

Potential Difference

Energy transferred to a given amount of electric charge.

Potential difference

The difference in electric potential between two points in an electric field; the work that has to be done in transferring unit positive charge from one point to the other, measured in volts

Potential energy

The energy of a body or system as a result of its position in an electric, magnetic, or gravitational field. It is measured in joules (SI units), electronvolts, ergs, etc.

Pressure

The amount of force applied on a certain area.

Proton

A stable, positively charged elementary particle, found in atomic nuclei in numbers equal to the atomic number of the element. It is a baryon with a charge of 1.602176462 × 1019 coulomb, a rest mass of 1.672 62159 × 1027 kilogram, and spin.

Radiation

The emission or transfer of radiant energy as particles, electromagnetic waves, sound, etc.

Reflection

When waves bounce back once they hit smooth surfaces.

Reflection

The act of reflecting or the state of being reflected.

Refraction

The change of direction and speed of waves when they travel across a different medium.

Refraction

The change in direction of a propagating wave, such as light or sound, in passing from one medium to another in which it has a different velocity.

Resistance

Potential difference divided by current. The unit is Ohms.

Resistance

The opposition to a flow of electric current through a circuit component, medium, or substance. It is the magnitude of the real part of the impedance and is measured in ohms.

Resultant Force

A single force on an object that has the same effect as all the forces acting on it.

Scalar

A quantity with magnitude but not direction.

Specific Heat Capacity

Energy needed for one kilogram of a substance to be raised by 1 degree Celsius.

Sublimation

It is a process of transformation in which solid directly changed to gas without passing through an intermediate liquid phase.

Superconductivity

The property of certain substances that have no electrical resistance. In metals it occurs at very low temperatures, but higher temperature superconductivity occurs in some ceramic materials.

Thermometer

A device used to measure the temperature.

Vector

A physical quantity which has magnitude and direction.

Vector

Vector is a quantity, which has both magnitude and direction.

Volt

The derived SI unit of electric potential; the potential difference between two points on a conductor carrying a current of 1 ampere, when the power dissipated between these points is 1 watt.

Voltmeter

A device used to measure voltage or potential difference.

Watt

The derived SI unit of power, equal to 1 joule per second; the power dissipated by a current of 1 ampere flowing across a potential difference of 1 volt. 1 watt is equivalent to 1.341 × 103 horsepower.

Wave

One of a sequence of ridges or undulations that moves across the surface of a body of a liquid, esp. the sea: created by the wind or a moving object and gravity.

Wavelength

The distance, measured in the direction of propagation, between two points of the same phase in consecutive cycles of a wave.

Waves

Disturbances that transfer energy from one place to another.
