Lesser-Known Concepts Of Physics

We know that Newton's law, Kepler's law, Carnot's theorem, thermodynamics and many other commonly heard laws and concepts had gained recognition since they form the basis of physics. These commonly known concepts are known by everyone who studies science since it is elementary to know for the sake of knowledge and examinations too. 

There are some lesser-known concepts which convey important concepts that we should know. In this article, we shall learn and understand two such concepts, Casimir Effect and Hubbles Law. 

Force Between Surfaces In A Vacuum

As we are aware, the force of attraction is seen among the objects on the earth. Do you know the force of attraction exists in a vacuum too? Casimir Effect explains that "The attractive force exists in a vacuum between two surfaces". This theory was first predicted by Hendrik Casimir, the Dutch Physicist. This theory holds for the molecular forces to cosmology and elementary particles of physics.

Casimir effect is explained as a feeble attractive force that is present between two close parallel uncharged conducting plates. This force is developed due to the quantum fluctuation of the electromagnetic field.

Applications of the Casimir effect are:

• They are used in the nanotechnology sector mainly for silicon integrated technology. 

• Casimir effect has contributed to the development of applications regarding the advancement of levitating devices.

• Casimir effect helps to understand the chiral bag model of the nucleon in the best way.

Now let us understand the Hubbles Law and its formula. 

Law On Velocity Of The Galaxy

Before we know about Hubbles law, let us know what is meant by redshift. Redshift is a phenomenon in which the electromagnetic radiations from an object undergoes an increase in wavelength. Redshift is the fundamental concept to be understood for astronomers.

Blueshift is the opposite phenomenon of redshift. Blueshift is also known as negative redshift where the energy increases due to shorter wavelengths.

Redshift occurs due to:

• The movement of objects either closer or apart from each other in space, i.e. the Doppler effect.

• Strong gravitational forces result in gravitational redshift.

• Cosmological redshift is an expansion of space such that objects are separated without the change in their position.

In the year 1929, Edwin Hubble observed the relation between distance and recession velocity of galaxies and developed the law. Hubbles law is also known as Hubble-Lemaitre law. Hubbles law states that "The velocity of the galaxy which is also known as the redshift is directly proportional to its distance".

The value of Hubble's constant was determined by Planck and found it to be equal to 46,200 mph per million light-years. 

The law is mainly used for studying the motion of the astronomical objects due to the expansion of the universe. Hubble's law was first used for understanding the expansion of the universe and is used as the evidence for the big bang model. Hubble's law is also used for analysing the dark matter and dark energy.

These laws and theories are some of the best contributions to the field of Physics. These concepts help to understand the fundamental molecular topics and also the vast universe and galaxies.

Electronic Devices and Their Uses

Diodes

A diode is a two-terminal semiconductor device that allows current to flow in only one direction. In other words, a diode is a unidirectional device. When the anode voltage is more positive than the cathode voltage, the diode is said to be forward-biased. Similarly, when the cathode voltage is more positive than the anode, the diode is reverse-biased. 

Uses of Diodes

One of the diodes’ core applications lies in blocking the current in one direction while allowing the current in the opposite direction. There are different types of diodes, and they are all used in numerous ways for various applications. Some of the applications of diodes are listed below:

• Diodes are widely used in transforming alternating current into direct current. 

• Diodes are used in surge protectors as they can prevent a spike in voltages.

• Diodes are used in digital logic.

• Zener diodes are used as voltage regulators. 

• Varactor diodes are used in electronic tuning.

Transistors

A transistor is a semiconducting device that can either act as a switch or an amplifier. Transistors control and regulate the flow of electronic signals. Transistors consist of three pair of terminals, and they are named as follows:

• Base 

• Collector 

• Emitter

There are mainly two types of transistors, and they are named as follows:

• Bipolar Junction Transistors

• Field-Effect Transistors

Uses of Transistors

In our modern society, extensive electricity use has encouraged transistors’ various benefits in almost every electronic circuit. Some of the applications of transistors are listed below:

• Transistors are widely used for switching and amplification purposes.

• Heterojunction Bipolar Transistors (HBT) can provide faster switching speeds and are used in analog and digital microwave applications.

• Schottky Transistors prevent transistors from saturating by diverting high input current.

Rectifiers

Rectifiers are electronic devices that convert alternating current to direct current. Rectifiers are mainly classified into two types:

• Controlled Rectifiers

• Uncontrolled Rectifiers

Controlled rectifiers are those whose voltage can be controlled and varied based on the application. There are two types of controlled rectifiers, and they are named Half Wave Controlled Rectifiers and Full Wave Controlled Rectifiers. We use SCRs, MOSFETs and IGBTs to make an uncontrolled rectifier a controlled one. 

Uncontrolled rectifiers are a type of rectifier whose voltage cannot be controlled. Uncontrolled rectifiers are further classified as Half wave rectifiers and Full wave Rectifiers. Let us learn more about these two types of rectifiers and their applications in real life.

Half Wave Rectifiers

A half-wave rectifier transforms an AC into a DC. For this transformation, a half-wave rectifier uses only one diode. This type of diode allows the one-half cycle of an AC voltage waveform to pass while blocking the other half cycle. Due to this functionality of half-wave rectifiers, they are used in the following applications:

• They are used in signal peak applications.

• They are used for signal demodulation purposes.

Full Wave Rectifiers

A full-wave rectifier is defined as a rectifier that converts the complete cycle of alternating current into pulsating DC. Unlike the halfwave rectifier that utilizes only the halfwave of the input AC cycle, the full-wave rectifier utilizes the full cycle. The full-wave rectifier can overcome the lower efficiency of the half-wave rectifier.

Advantages of Full Wave Rectifiers

The rectification efficiency of full-wave rectifiers is double that of half-wave rectifiers. The ripple factor in a full-wave rectifier is lower.

Significance of Compound Interest and Simple Interest

In mathematics, we have learned a huge number of concepts that are directly or indirectly related to our daily lives. Whether we have studied numbers, shapes, measurements, arithmetic operations, etc., each concept has its own significance in real life and in various fields such as engineering, medical, banking, etc.

The most common concept we deal with is the calculation related to the currencies, such as saving and investing and getting the interest in the principal amount. Interest is characterized as the expense of getting cash on account of revenue charged on a credit balance. Alternatively, interest can likewise be the rate paid for cash on the store as on account of authentication of the store. So basically there are two types of interest: Simple interest  and Compound interest.

Simple Interest

The method of calculating interest for a principal or loan amount is known as simple interest. Whenever we lent money to the bank or deposited some principal amount, then the bank impose some interest at a rate annually. Even if we borrow any amount from the bank, then they need to return or repay the loan amount along with interest. The simple interest formula is given by:

SI = (P x R x T)/100

Where P is the principal amount (in Rs.), R is the rate of interest (in %) and T is the time period (in years).

With simple interest credits, the loan specialist applies the installment to the month's advantage first; the rest of the installment decreases the head. Every month, the borrower cover the premium with the goal that it never builds. In the event that she pays her credit late, she'll need to pay more cash to cover the extra premium and keep the advance's predefined result date. This differentiations with self multiplying dividends, which adds a part of the old interest to the advance. The loan specialist at that point computes new interest on the old interest owed by the borrower.

Compound interest

Compound interest is the sum of interest on principal amount and interest added to the previous period. Hence, it is said to be interest compounded annually. Compound interest is the expansion important to the chief amount of a credit or store, or all in all, interest on interest. It is the consequence of reinvesting premium, instead of paying it out, so that premium in the following time frame is then acquired on the chief entirely in addition to recently collected revenue.

Compound interest = Amount - Principal

Amount = P(1+r/n)nt

P= principal

R= rate of interest

n= number of times the interest is compounded yearly

Some of the major applications of compound interest are seen in increase and decrease of population, growth of bacteria and rise or depletion of population, etc.

As we have learned about simple and compound interest in this article, thus we can conclude that both are very important in our day to day life. 

Causes and Effects of Flood

Flood occurs when water inundated land that is usually dry, which can happen in a multitude of ways. A flow, spreading over the surrounding property, called a floodplain, may be flooded by heavy rain, a ruptured dam or levee, rapid melting of snow or ice, or even an unfortunately located beaver dam. Human factors raise flood risk like urbanisation, since there are more impermeable surfaces in cities and towns. Deforestation since the destruction of trees decreases the quantity of intercepted water and increases run-off.

Due to enhanced denitrification during anaerobic soil conditions that continue during flooding, flooding often causes soil nitrogen loss. For crop development, nitrogen is essential, and most farmers apply some additional nitrogen to their crops. Effects of flood can drastically alter the amount of nutrients in the soil available to plants. Soil lost due to erosion will take with it important nutrients and organic matter that are available to plants. Flood sediment deposition can increase soil levels of phosphorus, nitrogen, silicon, and potassium.

What are the Causes of Floods?

Floods are caused for many reasons, strong and prolonged precipitation, heavy moulting of snow, changes in the flow of a river, silting of river beds, collapse of dams, landslides, erosion, unscientific land use and tsunamis. 

An overflow of water on usually dry land is a flood. Most often, this is due to an overflowing river, a dam failure, snowmelt, or heavy precipitation. Tsunamis are less common, and storm surges are less common. People attempt to transfer themselves and their most valuable possessions to safer ground quickly during a storm.

In the catchment areas of rivers and in badly drained areas, heavy rainfall is the main causes of flood. If the water level increases above the banks or dams of the river, the water begins to flood. Floods can look very different because anywhere from a few inches of water to several feet is submerged by flooding.

Health Impacts of Floods

Injuries, diseases, poisoning and greater problems with mental wellbeing are health consequences observed during and after floods. Infectious disease outbreaks are uncommon. Millions of people will be affected by sea level rises and storm surges, which cause coastal flooding. Naturally, flooding occurs along every river and coastal region. Flood waters can carry nutrient-rich sediments that contribute to vegetation in a fertile setting. By providing a range of habitats for fish and other species, the floodplains are beneficial for wildlife.

Contamination of the supply of drinking water is the principal cause of waterborne diseases during flooding. Floods introduce bacteria, parasites and viruses into the drinking water system, resulting in waterborne disease outbreaks. Atmospheric conditions that lead to heavy rain or the rapid melting of snow and ice cause extreme flooding. Geography may also make it more likely that a region would flood.

Instead, disasters show the vulnerability or susceptibility of people when faced with floods, cyclones, volcanic eruptions, landslides, or other potentially harmful natural phenomena. Small barriers in ditches and fields, or notches cut into embankments, both of which channel the water into open land, are natural flood defence features.

Analgesic and Uses of Aspirin

Analgesics are a class of drugs specifically intended to ease pain. These include acetaminophen, which, when combined with another drug, is available over the counter or by prescription, and narcotics, which are only available by prescription. Analgesics are a category of medicines used to alleviate analgesia. They function by suppressing the brain's pain signals or by interfering with the processing of those signals by the brain. Analgesics are broadly classified as pain relievers that are either non-narcotic or narcotic.

Aspirin is a common medication also known as acetylsalicylic acid. It is an NSAID that treats inflammation and prevents blood clots from forming. For this purpose, in addition to treating moderate pain or fever, it may be used to minimise the risk of strokes and heart attacks. Aspirin uses includes conditions such as muscle aches, toothaches, common colds, and headaches to minimise fever and alleviate mild to moderate pain. Aspirin is known to be a salicylate and an anti-inflammatory nonsteroidal drug.

Analgesic Effect of Aspirin

Aspirin acts by, among other things, blocking the development of prostaglandins, the on-off switch in cells that control pain and inflammation. This is why aspirin prevents moderate pain and inflammation. Aspirin is known to be a salicylate and an anti-inflammatory nonsteroidal drug. This soothes pain and reduces swelling.

In patients who have cardiovascular disease or who have already had a heart attack or stroke, aspirin has been shown to be effective when used daily to reduce the risk of heart attack, clot-related strokes and other blood flow issues. Aspirin is prescribed for these purposes by many medical practitioners.

There are two types of analgesics, anti-inflammatory drugs that relieve pain by decreasing local inflammatory responses, and opioids that operate on the brain. Since they can induce sleep, opioid analgesics were once considered narcotic drugs. Aspirin, by acetylation with acetic anhydride, is prepared by chemical synthesis from salicylic acid. Many of the salicylates, while their anti-platelet activity is unique, share the same properties as aspirin.

Aspirin Mechanism of Action

Aspirin has many effects in the body, primarily inflammation reduction, analgesia, clotting prevention, and fever reduction. Although it is safe for most adults to use an occasional aspirin or two for headaches, body aches or fever, frequent aspirin use may have severe side effects, like internal bleeding. 

Aspirin is a non-steroidal antiinflammatory agent given orally. Acetylsalicylic acid binds to serine residues in cyclooxygenases and acetylates them, resulting in reduced prostaglandin, platelet aggregation, and inflammation synthesis. This agent exhibits properties of analgesic, antipyretic, and anticoagulant.

In high-risk patients, low-dose aspirin is considered to minimise the risk of heart attack. Lowering high blood pressure also tends to improve, but studies looking at this effect produce confusing results. There may now be a reason for this: aspirin decreases blood pressure only when taken at bedtime. A second stroke or a transient ischemic attack, which is also a warning sign of a stroke, may help avoid aspirin. For persons who have never had a stroke or heart attack.