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 Regulator

The DEVICE used to CHANGE the SPEED of an ELECTRIC FAN is regulator.

 MOMENTUM

A cricketer lowers his hands while taking a CATCH to DECREASE the RATE of momentum. CRICKETERS increase the time by pulling their hand's backward with the ball while taking a catch. Linear momentum or translational momentum is the product of the mass and velocity of an object.

 Soil

Soil cannot be USED for MAKING LENSES.

 Reduce the friction between the wheel and the axle

The PURPOSE of a ball bearing is to reduce rotational friction and SUPPORT RADIAL and axial LOADS. Reduce the friction as rolling friction is the least, rather than SLIDING or static friction.

 It is ALWAYS POSITIVE

Displacement can be EITHER positive or NEGATIVE.

 Henry/METER

In SI UNITS, PERMEABILITY is measured in Henry PER meter (H/m).

 SOUND SIGNAL into CURRENT signal

Microphone is a DEVICE which TRANSFORMS the sound signal into current signal.

 Only proportional REGION of the stress strain curve

The HOOKE's law is VALID only when the stress is proportional to the strain, that is only in the PROPORTIONALITY limit.

 Good ABSORBER and good radiator of HEAT

The earth is a good absorber and good radiator of heat.

 Power source

The power source such as a Battery of an IED creates an ELECTRICAL charge. An Improvised EXPLOSIVE Device (IED) is a bomb constructed and DEPLOYED in ways other than in CONVENTIONAL MILITARY action.

 3 to 30 MHz

High frequency (HF) is the ITU designation for the RANGE of RADIO frequency electromagnetic waves (radio waves) between 3 and 30 megahertz (MHz). It is also known as the decameter band or decameter wave as its wavelengths range from one to ten DECAMETERS (ten to one hundred METERS).

 Bernoulli's principle

The fact that two large SHIPS travelling on close parallel courses in the same direction tend to move towards each other can be explained by Bernoulli's principle. The rapid flow of AIR between the two moving ships causes a reducton of pressure (Bernoulli's principle) , so they (the ships) are DRAWN closer together.

 Atmospheric REFRACTION

Atmospheric refraction is the reason behind the twinkling of stars. The starlight on entering earth surface UNDERGOES refraction continuously before it reaches to earth. The starlight bend towards the normal as it ENTERS from RARER to denser medium. The air near the earth surface is denser than upper layers. Therefore the apparent position of the stars are slightly different from its actual position, when it is viewed from horizon. The apparent position of stars are not stationary and keeps on changing slightly, because the physical condition of the atmosphere are not stationary. Because of this the stars sometimes appears brighter and sometimes appear FAINTER.

 NYLONS

The PLASTIC material COMMONLY used for making gear wheels is nylons.

 SURFACE tension

The SEPARATION of OIL and water is caused due to the difference in surface tension of the TWO liquids. The water MOLECULES stick together tightly and does not mix with the oil because water molecules are attracted to each other very strongly, forming an invisible “skin” of surface tension around each drop.

 They OBSERVE inverse square law

It is a UNIVERSAL attractive force. It is directly proportional to the product of the masses of the two BODIES. It obeys inverse square law. It is a long RANGE force and does not need any intervening medium for its operation.

 FALLS suddenly

A storm is predicted if atmospheric PRESSURE falls suddenly.

 Reach a PARTICULAR height and remain floating

A balloon FILLED with the hydrogen stops RISING after it has attained a CERTAIN height in the sky. This is because as height increases, the density of air decreases resulting in a decrease of buoyant force.

 Nuclear PHYSICS

Particle physics STUDIES the nature of particles, while nuclear physics studies the ATOMIC NUCLEI.

 0.5

u(INITIAL velocity) = 25m/s
v(final velocity) = 30m/s
t(TIME) = 10s

a = (v-u)/t
a = (30-25)/10
a = 5/10
a = 1/2
a = 0.5m/s²

 Virtual, magnified and erect

A BASIC microscope is made up of two converging lenses. The first lens creates a real image which serves as the OBJECT for the second lens, and the image created by the second lens is the ONE a viewer SEES. The FINAL image is magnified, virtual and is inverted compared to the original object.

 DECREASES with DECREASE of temperature

The velocity of SOUND in air decreases with decrease of temperature.

 Cool air falls down

In convection, hot air rises from the EARTH's surface and becomes COLD at higher altitude because of lower temperature there. As it cools, it sinks down to the surface of the Earth. On reaching Earth, it warms again and rises up again. The main reason for this phenomenon is - SINKING cold air PUSHES the warm air up.

 Scuba diving

Scuba diving PLAYERS MUST have the KNOWLEDGE of Pascal's law.

 SCATTERING

Stars APPEAR TWINKLING because of scattering of LIGHT.

 Low temperature, high pressure

The DENSITY of GASES depends upon the temperature. The HIGHER the temperature, the more the MOLECULES are spread out and the lower the density.

 14 m/s

14 m/s.

 Crooks GLASS

A type of glass that contains cerium and other rare EARTHS and has a high absorption of ultraviolet radiation is used in sunglasses. Sunglasses or sun glasses are a form of protective eyewear designed primarily to prevent bright sunlight and high-energy visible light from damaging or discomforting the eyes. They can sometimes also function as a visual aid, as variously TERMED spectacles or glasses exist, featuring lenses that are coloured, polarized or darkened. In the early 20th century they were also known as sun cheaters. The colour of the lens can vary depending on style, FASHION, and purpose, but for general use, red, grey, green, or brown are recommended to avoid or minimize colour distortion, which could affect safety when, for instance, driving a car or a school bus.

 LESS THERMAL CONDUCTIVITY

A metal to be USED as a COOKING material should have less thermal conductivity.

 INFRARED RAYS

Every HOT OBJECT EMITS infrared rays.

 Either equal to or greater than 1

While ascending a hill GEAR RATIO should be “Either equal to or greater than 1. Gear Ratio is the ratio between angular velocity of input gear to the angular velocity of OUTPUT gear. It PREVENTS the vehicle from stalling.

 Thomas Alva Edison

Radio is the transmission of signals through free space by ELECTROMAGNETIC radiation of a frequency significantly below that of visible light, in the radio frequency range, from about 30 kHz to 300 GHz. These WAVES are called radio waves. Experiments were undertaken by Thomas Edison and his EMPLOYEES of MENLO Park. Edison applied in 1885 to the U.S. Patent Office for a patent on an electrostatic COUPLING system between elevated terminals. The patent was granted as U.S. Patent 465,971 on December 29, 1891. The Marconi Company would later purchase rights to the Edison patent to protect them legally from lawsuits.

 Decreases

When detergent is added to WATER, it decreases the surface tension of the water. COMPOUNDS that lower water's surface tension are called surfactants, which work by separating the water MOLECULES from one ANOTHER.

 Concave mirror

Concave MIRRORS are used in search lights and TORCHES so that we have a more focused light beam which will not DIVERGE out and HENCE help in searching. It is used for different light RAYS falling on it to a single point.

 STOPE

Batholith is the biggest of the INTRUSIVE IGNEOUS rocks. Stope is not an intrusive igneous body. It is related to mining.

 Decreases with increase in temperature

According to Wien’s DISPLACEMENT law, when the temperature of a blackbody radiator increases, the overall radiated energy increases. Wavelength of MAXIMUM EMISSION from a blackbody is inversely proportional to its temperature. Shorter-wavelength (higher-frequency) light CORRESPONDS to higher-energy photons.

 Rainfall

Barometer is instrument which is USED to measure to pressure. A slow DOWNFALL of reading suggests a low pressure area is passing in a nearby REGION, it may rain. If the reading is going down very FAST then its an indication of STORM (within 5-6 hours).

 A SINGLE TRANSISTOR

A NOT GATE can be IMPLEMENTED by a single transistor.

 Concave mirror

Concave mirrors are used in head lights of vehicles because when the bulb of headlight is PLACED at FOCUS of concave mirror it will ALLOW the LIGHT to spread out to infinity after the reflection on the mirror.

 The Sun remains behind us and we face raindrops

We see rainbows because of the geometry of raindrops. When the sun shines from behind us into the rain, incident rays of light ENTER the drop and are refracted inwards. They are reflected from the back surface of the raindrop, and refracted again as they exit the raindrop and return to our eyes. A rainbow is an OPTICAL and meteorological phenomenon that is caused by reflection of light in WATER droplets in the EARTH’s atmosphere, resulting in a spectrum of light APPEARING in the sky.

 WHITE hole

A White Hole is a hypothetical hole in outer space from which energy, STARS, and other CELESTIAL MATTER emerge or explode. It is a theoretical celestial object into which matter is funneled from a black hole.

 Energy

An object having the capability to do WORK is SAID to POSSESS Energy.

 RADIATION

Energy TRAVELS from SUN to EARTH through radiation.

 BECOMES 1/4 th

When VELOCITY is HALVED, its KINETIC ENERGY becomes 1/4th.

 PYRANOMETER

Instruments for MEASURING SOLAR RADIATION is Pyranometer.

 MICROPHONE

The device which CONVERTS SOUND ENERGY into ELECTRICAL energy is called microphone.

 Frequency of transmitted signal

A television channel is a PHYSICAL or VIRTUAL channel over which a television station or television network is distributed. Channel numbers represent actual frequencies used to BROADCAST the television signal. For example, in North America, “channel 2” refers to the broadcast or cable BAND of 54 to 60 MHz, with carrier frequencies of 55.25 MHz for NTSC analog video (VSB) and 59.75 MHz for analog audio (FM), or 55.31 MHz for digital ATSC (8VSB).

 CONDUCTANCE

Ampere SECOND COULD be the UNIT of conductance.

 A HIGH RESISTANCE in series

A galvanometer is CONVERTED into a voltmeter by CONNECTING with high resistance.

 HELIUM

Nuclear fusion, the source of all the ENERGY so generously radiated by the SUN, does two THINGS: it converts hydrogen into helium (or rather, makes helium nuclei from PROTONS) and it converts mass to energy.