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 Amplitude

Amplitude DETERMINES the FREQUENCY of a SOUND WAVE.

 DETECTING and locating the POSITION of OBJECTS such as AEROPLANES.

RADAR is USED for detecting and locating the position of objects such as Aeroplanes.

 Inertia of motion

Newton's 1st law of inertia states that an OBJECT will change its direction when a force is applied to it. Hence, when a BUS takes a SUDDEN turn the passengers are thrown outward. This is due to the inertia of direction.

 Undergoes least deviation

The PRIMARY reason why the colour red is used for danger signals is that red light is scattered the least by air molecules. The effect of SCATTERING is INVERSELY related to the fourth power of the wavelength of a colour. Therefore blue which has the least wavelength of all the VISIBLE radiations is scattered the most and red which has the highest wavelength of all the colours we can see is scattered the least. So red light is able to travel the longest distance through fog, rain, and the alike. Also, red is a colour we inherently perceive as one that is associated with danger.

 Borax

Traditionally borax was USED as a flux for brazing, but there are now many different fluxes available, often using active CHEMICALS such as FLUORIDES as well as wetting AGENTS.

 February 28

'National Science DAY' is CELEBRATED in India on February 28.

 Shearing stress to shearing strain

The modulus of rigidity, also known as SHEAR modulus, is DEFINED as the ratio of shear stress to shear strain of a structural MEMBER. This PROPERTY depends on the material of the member: the more elastic the member, the higher the modulus of rigidity.

 25 W

When CONNECTED in series, the VOLTAGES divide in them in the RATIO of their resistances. The voltage of 440 V devides in such a way that voltage ACROSS 25 w bulb will be more than 220 V. Hence 25 w bulb will fuse.

 The LOCATION of the load

Second and third CLASS LEVERS are differentiated by the location of the load.

 Inertia of motion

When a running car stops suddenly, the PASSENGER tends to LEAN forward because of inertia of motion. according to Newton's 1st law of motion, every BODIES have nature to maintain inertia of REST or motion until there is no net force applied on that body.

 Move towards B

Since we KNOW that ELECTRIC currents move from a higher POTENTIAL or a LOWER potential. Also, electrons move in the direction opposite to electric current. So the ELECTRON on the line joining two points A and B will move from lower to higher potential i.e, it will move towards B.

 Bicycle

Bicycle is an example of COMPOUND MACHINE. A compound machine is a combination of TWO or more simple MACHINES.

 surface tension

The MATERIAL of rain PROOF coats have the PROPERTY of not minimizing the surface tension which will tend the WATER molecule to be in its drop form.

 Liquified

An ideal GAS have no INTERMOLECULAR FORCE of attraction, so it cannot be liquefied by applying high pressure and decreasing temperature.

 ELECTROMAGNETIC radio wave frequencies

The hertz (Hz) is defined as one cycle per second and is a SI UNIT of frequency. Here KILOHERTZ is ALSO a unit of frequency of waves and is defined as 1000 cycles per second. Radio waves are measured in kilohertz (KHz).

 6 UNITS

 Mutual INDUCTION

A transformer consists of two electrically isolated COILS and operates on Faraday's principal of “mutual induction”, in which an EMF is induced in the transformers secondary coil by the MAGNETIC flux generated by the voltages and currents flowing in the primary coil WINDING.

 0°C

Freezing point is the TEMPERATURE where a LIQUID converts into solid. WATER converts into ice at zero degrees CENTIGRADE. So degree zero centigrade is the freezing point of water.

 NEWTON's THIRD LAW

Rocket WORKS on the PRINCIPLE of Newton's Third Law.

 Adiabatic process

When a tyre bursts SUDDENLY energy is not IMMEDIATELY TRANSFERRED between the system and the surrounding. So the process is adiabatic. There sudden expansion of its AIR into the atmosphere is adiabatic and the tyre is COOLED. In adiabatic process, heat neither enters the system nor leaves the system.

 WATT

The UNIT of ELECTRICAL POWER is Watt.

 Mica

Mica is a GOOD CONDUCTOR of HEAT but BAD conductor of ELECTRICITY.

 Its wavelength is the longest

DANGER SIGNALS are red in color because it is scattered the least by air molecules. Since the color red has the HIGHEST wavelength of all the colors we can see it scattered the least. So, red light is used as a danger signal as it is able to travel the longest distance through the fog, RAIN, ETC.

 Chemical ENERGY

Electric energy is CONVERTED into chemical energy and stored it as chemical energy WITHIN the CELLS.

<P> R/5

1st copper wire: R = PL/A = pl/ πr2
2ndcopper wire: R’ = p’L’/A’ = pl/(4 πr2) = R/4
If JOINED in parallel, (1/Req) = (1/R) + (1/R’)
= 1/R + 4/R
= 5/R
Req = R/5

 NEGATIVELY charged

Electrons CARRY CURRENT in a good conductor of ELECTRICITY and they are negatively charged. This MAKES a good electrical conductor negatively charged.

 Conservation of momentum

Rocket works on the principle of conservation of momentum. Rocket ejaculates gases in backward DIRECTION which CREATES momentum of the gases backwards and thus by conservation of momentum, the rocket gets a momentum in the FORWARD direction MAKING it to move forward.

 Sphere

The sphere will reach the BOTTOM faster than the DISK. It is because the disk has a higher rotational inertia than the solid:
I= mr²
I is the rotational inertia where m is the MASS and r is the square of distance from the axis of rotation. in the case of disk I is greater due to r and more the I, more is the rotational K.E. Then for conservation of energy Translational K.E will be less.
mgh= K.E (T) + K.E (R)
so in case of sphere translational K.E will be more, meaning more FINAL velocity and it will reach the bottom faster.

 Homogeneous and transparent

Light travels in a STRAIGHT LINE (rectilinear propagation of light). This statement does hold if the MEDIUM of travel for light is homogeneous and transparent.

 Soft iron

Soft iron provides the BEST material for the core of a TRANSFORMER as its permeability (μ) is very high. Its hysteresis curve is of small area and its COERCIVITY is very LOW.

 CENTRIFUGATION

A washing machine by spinning at 800-1600 rpm helps soap and DIRT with it to leave the surface of the CLOTH via CENTRIFUGAL force and into outlet pipes hence utilizing centrifugation to both clean and partially dry the clothes loaded in it.

 POTENTIAL ENERGY

An OBJECT at REST MAY have Potential energy.

 interference

On a rainy day, small OIL films on water show brilliant COLOURS. This is due to Interference.
Interference is a phenomenon in which two waves superimpose to form a RESULTANT wave of GREATER, LOWER or same amplitude.

 3600 JOULES

1 WH (WATT HOUR) = 3600 joules

 ROUGH BLACK

 Low voltage A.C. into high voltage A.C.

A TRANSFORMER is an electrical DEVICE that transfers energy from one circuit to another by magnetic coupling with no moving parts. It converts high voltage AC into low voltage AC and vice-versa. It is based upon the PRINCIPLE of mutual induction. Transformers alone cannot convert AC to DC or DC to AC; besides, they cannot change the voltage or current of DC.

 KINETIC ENERGY

Kinetic energy is the energy of MOTION.

 It is a POOR conductor of HEAT

Cotton CLOTHES are thin and do not have space in which air can be trapped. Thus, cotton clothes do not prevent heat coming out of our body. Woollen clothes keep us warm during WINTER because wool is a poor conductor of heat and it has air trapped in between the fibres.

 Compact FLUORESCENT lamp

A compact fluorescent lamp (CFL), ALSO called compact fluorescent light, energy-saving light and compact fluorescent tube, is a fluorescent lamp designed to REPLACE an incandescent light bulb; some types FIT into light fixtures designed for incandescent BULBS.

 Tungsten

The filament of an electric bulb is made of tungsten because it has some amazing properties including the HIGHEST melting point (3422^oC), lowest VAPOR PRESSURE, and greatest TENSILE strength out of all the metals.

 Pressure varies

The BOILING point of a liquid varies according to the APPLIED pressure; the normal boiling point is the TEMPERATURE at which the vapour pressure is equal to the standard sea-LEVEL atmospheric pressure (760 mm [29.92 inches] of mercury). At sea level, water BOILS at 100°C (212°F).

 Dissociation of electrolytes

The electrolyte consists of a solvent (WATER, an organic liquid, or even a solid) and one or more chemicals that dissociate into ions in the solvent. These ions serve to deliver ELECTRONS and chemical matter through the cell interior to balance the flow of electric current outside the cell during cell operation. An electrolyte is a liquid or gel that contains ions and can be DECOMPOSED by ELECTROLYSIS, e.g., that present in a battery. Commonly, electrolytes are solutions of acids, BASES, or salts. Electrolyte solutions can also result from the dissolution of some biological (e.g., DNA, polypeptides) and synthetic polymers (e.g., polystyrene sulfonate), termed poly-electrolytes, which contain charged functional groups.

 OTTO-cycle

A FOUR-stroke engine (also known as four-cycle) is an INTERNAL combustion engine in which the piston completes four SEPARATE strokes—intake, compression, power, and exhaust—during two separate revolutions of the engine’s crankshaft, and one single THERMODYNAMIC cycle. The earliest of these to be developed is the Otto cycle engine developed in 1876 by Nikolaus August Otto in Cologne, Germany, after the operation principle described by Alphonse Beau de Rochas in 1861.

 RECIPROCATING

The reciprocating COMPRESSOR is the most POPULAR TYPE of AC compressor.

 All of the above

When an unbalanced force ACTS on an OBJECT it causes CHANGE in motion of the object, the speed and DIRECTION of the object changes and the object MOVES.

 Decreases SLIGHTLY

Tap WATER is PLACED in an open pad and allowed to evaporate. After some TIME the temperature of water decreases slightly.

 Centrifugal forces

The spin DRYER is probably the most familiar centrifuge. The spin dryer of a washing machine removes excess water from the CLOTHING by rotating at a HIGH speed. The high speed of rotation CREATES a high centrifugal force for the water in the clothing which CAUSES it to be pulled to the outside of the spinning portion of the washing machine and away from the clothes.

 Bridge

A CANTILEVER is a beam anchored at only one end. The beam carries the LOAD to the support where it is resisted by moment and shear stress. Cantilever construction allows for overhanging STRUCTURES without external bracing. Cantilevers can also be constructed with trusses or slabs. This is in contrast to a simply supported beam such as those found in a post and LINTEL system. A simply supported beam is supported at both ends with loads applied between the SUPPORTS. Cantilevers are widely found in construction, notably in cantilever bridges.

 Lead-37%, tin-63%

The COMPOSITION of ELECTRICIAN SOLDER is Lead-37%, tin-63%.

 Astronomical distance

One parsec is the distance to an object WHOSE parallax angle is one arcsecond. The RADIUS of the Earth's orbit equals one astronomical UNIT (AU), so an object that is one parsec distant is 206,265 AU (or 3.26 light-years) away.