Month: August 2023

Engine failure results in the loss of thrust, which is required for aircraft to maintain altitude or climb further. However, engine failure does not necessarily culminate into the complete loss of aircraft control. Aggressive use of flight controls, namely rudders and ailerons, can steer the flight to safety.

Aircraft compensate for a loss of thrust by losing altitude. They have a thrust-to-drag ratio of 10:1, which means they can fly 10 miles forward for every 1 mile lost in altitude. Cruising altitudes of 35,000 ft (~6 miles) give aircraft a distance of 60 miles to find a suitable place to conduct an emergency landing. Engine failure is easier to deal with at higher altitudes than at lower altitudes, such as when taking off.

Pilots faced with engine failure must conduct forced landings on the most favorable surface available to them. Here’s an interesting catch, this surface need not only be land. Airplanes can be ditched, i.e., landed on water or ice, without compromising passenger safety.

Similar to crumple zones in cars, aircraft have expendable parts in their structure to dissipate the force of landing in inclement terrain. These include the wings, landing gear, and even the bottom part of the fuselage.

– By Akash

Automobile engineers have been developing and marketing hybrid vehicles since the late 1800s; however, due to the higher cost involved in producing it on a massive scale, its popularity in the market still remains low. But car manufacturers continue to research and develop newer hybrid technology to comply with strict emissions norms.

A hybrid vehicle gets its energy simultaneously from a gasoline engine and an electric motor. The engine and the motor work together to power the car; this helps to increase your fuel economic rating (i.e. how many miles you can travel with one gallon of gasoline). The engine also uses gasoline to help recharge the vehicle’s battery, which powers the electric motor.

A plug-in hybrid vehicle (PHEV) also uses a gasoline engine and an electric motor, but in different ways. The plug-in hybrid runs primarily using its electric motor, powered by the battery. A plug-in hybrid won’t tap into your gas tank until the battery runs out of power. Instead of the electric motor and the engine working together at the same time, a plug-in hybrid uses its engine as a backup plan.The distance you can travel before this happens is often advertised as a vehicle’s all electric range. Once the battery runs out of power, it has to be charged using a plug-in electric charger; the engine does not recharge a plug-in hybrid’s battery.

– By Akash

A Nit (nt) is a unit that represents the intensity of visible light. Nits are commonly used to describe the brightness of video displays, such as LED panels. The name nit is believed to have come from the Latin nitere, a word meaning ‘to shine’.

One nit is equal to one candela per square meter. You may have seen light measures like candelas, lumens, lux, and others. But the nit, because it is a measurement of luminous intensity over a given area, makes it more useful for comparing relative brightnesses of displays even if they’re not all the exact same size. It is the measurement you are going to see most.

Another common measurement of light intensity, the lumen, is often used in rating projectors, so you may run across it. It is a measurement of reflected light at a distance from the reflecting surface. And because projectors are still often used in indoor venues, comparing nits and lumens can be useful. In round terms, 1 nit is equal 3.5 lumens (3.426 to be more exact).

A simple way to remember the difference between nits and lumens is that the nit is analogous to sunlight, direct light; while the lumen is more like moonlight, or reflected light.

– By Akash

Refresh rate is the frequency at which the screen updates with new images each second, measured in hertz (cycles per second). The content may look steady on the display, but what the viewer can’t see is how fast the content is changing — up to 360 times a second. The higher the refresh rate, the smoother the visual quality.

Super high monitor refresh rates aren’t all that important for office workers focused on lighter computing like word processing, spreadsheets and emails. But in more visual professions like creative production and game development, a high refresh rate for monitors is invaluable.

The standard refresh rate for desktop monitors is 60Hz. But in recent years, more specialized, high performing monitors have been developed that support 120Hz, 144Hz and even 240Hz refresh rates, which ensure ultra-smooth content viewing, even for the most demanding visual processing needs.

Just buying a high refresh rate monitor doesn’t mean the display quality will magically improve. The monitor’s refresh rate reflects the maximum rate at which the display can change the visuals. What happens on the screen depends on the frame rate of the output — the number of video frames that are sent to the display each second.

The majority of Movies, for example, are shot and produced at 24 frames per second (fps), so a 60Hz monitor will easily offer smooth playback. But having a 120Hz monitor (or even faster) won’t provide any visible benefit to playback quality.

Refresh rate is a measure of how many frames a monitor can refresh every second. FPS, however, is a measure of the ability of the graphics card to draw a number of frames on the display each second. While both are a measure of different things, they are directly related and affect each other.

– By Akash

The main difference between green tea and black tea is that black tea is oxidized during production while green tea is not.

Tea is an addictive beverage we all love. It is true that green and black tea varies in colour and taste. These differences are a result of their manufacturing process. During the process of black tea production, manufacturers first roll the tea leaves and then expose the tea leaves to air to enhance the oxidation process. Consequently, the leaves become dark brown, and the flavors get more intense. However, green tea has a relatively light colour and a milder taste than black. This is mainly because manufacturers focus on avoiding oxidation during the processing of green tea. Despite these differences, both varieties provide significant benefits to your health.

Green tea is a common variety of tea produced using the evergreen Camellia sinensis plant. In processing green tea, the manufacturers heat the leaves of green tea just after harvesting them in order to avoid the process of oxidation.

Geographically, green tea plantations can be mainly found in China and Japan. When it comes to brewing, we usually use water with a relatively low temperature to prepare green tea (at or around 175 degrees). Some Japanese green teas, such as Kabusecha and Gyokuro, require a much lower temperature, around 140 degrees.

Black tea is another variety of tea prepared by the leaves taken from the same plant Camellia sinensis. However, unlike the leaves of green tea, the manufactures completely oxidize the black tea leaves right after harvesting them. The process of oxidation turns the leaves into a dark brown or a black shade, unlike the green tea leaves, which preserve their natural green shade.

Currently, different varieties of black tea are mainly grown in India and China. Some of the world-famous black tea varieties are Assam, Golden Yunnan and Darjeeling. Further, Vietnam and Nepal are the other two large-scale black tea producing Asian countries in the world.

In contrast to green tea, when brewing black tea, we use boiling water at or around a temperature of 212 degrees. Moreover, we steep black tea for about 3-5 minutes.

– By Akash

White fabrics acquire a slight color cast after use (mainly grey or yellow). Since blue and yellow are complementary colors in the subtractive color model of color perception, adding a trace of blue color to the slightly off-white color of these fabrics makes them appear whiter. Laundry detergents may also use fluorescing agents to similar effect. Many white fabrics are blued during manufacturing. Bluing is not permanent and rinses out over time leaving dingy or yellowed whites. A commercial bluing product allows the consumer to add the bluing back into the fabric to restore whiteness.On the same principle, bluing is sometimes used by white-super people in a blue rinse.

Bluing has other miscellaneous household uses, including as an ingredient in rock crystal “gardens” (whereby a porous item is placed in a salt solution, the solution then precipitating out as crystals), and to improve the appearance of swimming-pool water.

Laundry bluing is made of a very fine blue iron powder suspended in water (a colloidal suspension).

Blue colorings have been added to rinse water for centuries, first in the form of powder blue or smalt, or using small lumps of indigo and starch, called stone blue. After the invention of synthetic ultramarine and Prussian blue it was manufactured by many companies. In many places, it has been replaced by bleach for its primary purpose.

– By Akash

Nitrocellulose (also known as cellulose nitrate, flash paper, flash cotton, guncotton, pyroxylin and flash string, depending on form) is a highly flammable compound formed by nitrating cellulose through exposure to a mixture of nitric acid and sulfuric acid. One of its first major uses was as guncotton, a replacement for gunpowder as propellant in firearms.

Guncotton was actually developed as a “Smokeless Gun Powder”, Essentially, the main difference between Black Gun Powder and Smokeless Gun Powder is that you need almost zero incombustible components. The key problem with black powder was that it produced a cloud of smoke, not only from uncombusted carbon but also, unavoidably, from ash, the salts formed from whatever anion happened to latch on to the sodium or potassium cations present from the nitrates in black powders. Black powder ash contains a high proportion of potassium or sodium sulfates and carbonates, and because the inorganic saltpeter component was about 2/3 of the total weight of black powder, you had a lot of ash.

Modern smokeless powder has to also have a couple of properties that make it useful over long periods of time: It must be relatively inert: you don’t want a substance like pure nitroglycerine that is shock sensitive. That property is for the primer (more on that below) and is a very bad idea for the propellant itself.

It must remain relatively inert: early smokeless gunpowders had volatile components like camphor that would evaporate after a few years, leaving a considerably less stable substance. Others had volatile components that would decompose over time and result in spontaneous explosions. It must at some point during the production process be Plastic: you need to be able to form the propellant into a useful shape to put it into a cartridge. It means that it needs to be able to fit a mold. Actual powders will do.

It must be explosive, but not too explosive: too high of a gas velocity and you get a high explosive, where the flame front exceeds the speed of sound and the stress on your gun barrel is very high. No one wants their gun to blow up in their faces.

– By Akash

Nitrocellulose (also known as cellulose nitrate, flash paper, flash cotton, guncotton, pyroxylin and flash string, depending on form) is a highly flammable compound formed by nitrating cellulose through exposure to a mixture of nitric acid and sulfuric acid. One of its first major uses was as guncotton, a replacement for gunpowder as propellant in firearms.

Guncotton was actually developed as a “Smokeless Gun Powder”, Essentially, the main difference between Black Gun Powder and Smokeless Gun Powder is that you need almost zero incombustible components. The key problem with black powder was that it produced a cloud of smoke, not only from uncombusted carbon but also, unavoidably, from ash, the salts formed from whatever anion happened to latch on to the sodium or potassium cations present from the nitrates in black powders. Black powder ash contains a high proportion of potassium or sodium sulfates and carbonates, and because the inorganic saltpeter component was about 2/3 of the total weight of black powder, you had a lot of ash.

Modern smokeless powder has to also have a couple of properties that make it useful over long periods of time: It must be relatively inert: you don’t want a substance like pure nitroglycerine that is shock sensitive. That property is for the primer (more on that below) and is a very bad idea for the propellant itself.

It must remain relatively inert: early smokeless gunpowders had volatile components like camphor that would evaporate after a few years, leaving a considerably less stable substance. Others had volatile components that would decompose over time and result in spontaneous explosions. It must at some point during the production process be Plastic: you need to be able to form the propellant into a useful shape to put it into a cartridge. It means that it needs to be able to fit a mold. Actual powders will do.

It must be explosive, but not too explosive: too high of a gas velocity and you get a high explosive, where the flame front exceeds the speed of sound and the stress on your gun barrel is very high. No one wants their gun to blow up in their faces.

– By Akash

Before we discover the reason, let us know about the Earth’s rotation. When seen from the North Pole, the Earth rotates anti-clock wise. It means in general term, from west to east as we see the sun rising in the east and setting in the west. The surface velocity of rotation varies from point to point on the Earth. It is about 1600 km per hour or about 460 meters in a second near the equator.

The velocity gradually reduces as we move to the poles and it is practically zero there. A satellite launched from the sites near the equator towards the east direction will get an initial boost equal to the velocity of Earth surface. This is similar to an athlete circling round and round before throwing a discus or a shot put. The initial boost helps in cutting down the cost of rockets used to launch the satellites.

This is the major reason for launching satellites in the east ward direction. But this benefit can be taken only for such satellites which are placed in geo-stationary orbit or which circle the Earth parallel to the equator. Such satellites are usually communication satellites or satellites used for scientific research such as ISS.

Another characteristic of launching satellites is that the launching stations are generally located near eastern coast line so that, just in case of failure of the launch, the satellite does not fall on built-up hinterland.

– By Akash

In today’s electronic warfare, survivability of fighter aircraft is of prime concern because of advancement in modern radar threats. To ensure survivability of aircraft, Counter Measure Dispensing System (CMDS) is used which provides passive jamming against infrared and radar threats.

Chaff is a passive expendable electronic countermeasure technology used worldwide to protect naval ships or fighter jets from enemy’s radar and Radio Frequency (RF) missile seekers. The chaff deployed in the air helps in misleading the enemy radars or deflecting adversary missiles.

The importance of this advanced chaff technology lies in the fact that very less quantity of chaff material deployed in the air acts as decoy to deflect enemy’s missiles for ensuring safety of the fighter aircraft. Ejection of the chaff payload is triggered either manually by the pilot or automatically by the CMDS.

– By Akash