This is the stopping force that opposes the relative movement or the tendency of relative motion of two solid surfaces, fluid layers, and material elements when they slide each other, known as friction. It acts tangentially along with the contact. Friction always exists in pairs. On microscopic observation, we find…
Friction is the force resisting the relative motion of solid surfaces, fluid layers, and material elements sliding against each other. There are several types of friction: Dry friction is a force that opposes the relative lateral motion of two solid surfaces in contact. Dry friction is subdivided into static friction…
We can understand sliding friction as the resistance force created between any two bodies when sliding against each other. This friction is also called kinetic friction and it is defined as the force that is required to keep a surface sliding along another surface. It hangs on two variables-…
When surfaces in contact move relative to each other, the friction between the two surfaces converts kinetic energy into thermal energy (that is, it converts work to heat). This property can have dramatic consequences, as illustrated by the use of friction created by rubbing pieces of wood together to start…
Chlorophyll is any of several related green pigments found in the mesosomes of cyanobacteria and in the chloroplasts of algae and plants. Chlorophyll allow plants to absorb energy from light. Chlorophylls absorb light most strongly in the blue portion of the electromagnetic spectrum as well as the red portion.…
A microorganism is a living organism that is so tiny it can only be seen with the aid of a microscope. Consider that the largest human cells are about the diameter of a human hair. Bacteria cells are one-hundredth the size of a human cell and viruses are much, much smaller again. If you imagine that…
Yeasts are eukaryotic, single-celled microorganisms classified as members of the fungus kingdom. Yeast is a very useful microorganism and is used to cause fermentation. Yeast grows by fermentation, feeding upon sugars. During fermentation, yeast converts glucose into ethanol and carbon dioxide and is therefore used in beer and wine…
Nitrogen gas is used for packing the packets of chips because it is an inert gas, and it prevents the oxidation of oils present in the chips. This keeps the chips fresh and has no or less breakage. Nitrogen is often filled in chips packets to prevent rancidity as it…
Thermal conduction is the transfer of internal energy by microscopic collisions of particles and movement of electrons within a body. The colliding particles, which include molecules, atoms, and electrons, transfer disorganized microscopic kinetic and potential energy when joined, known as internal energy. Conduction takes place in most phases: solid,…
Heat transfer is the transfer of heat or thermal energy between physical systems. So when there is a temperature difference between two bodies, heat is transferred from the hot body to the colder body. There are three common modes of heat transfer – conduction, convection, and radiation. In this article,…
Radiation The color of your home’s exterior influences a lot more than the look of your house. The outside of your house either absorbs or reflects heat, making the inside hotter or cooler. That means the color you select for the outside of your home affects the temperature inside,…
Osmosis is a vital process in biological systems, as biological membranes are semipermeable. In general, these membranes are impermeable to large and polar molecules, such as ions, proteins, and polysaccharides, while being permeable to non-polar or hydrophobic molecules like lipids as well as to small molecules like oxygen, carbon…
A well-known chemistry experiment is done by placing an egg (raw or boiled) into a container filled with Vinegar. After a few days, something exciting is observed: the egg becomes rubbery and bouncy. The eggshell is formed by calcium carbonate (CaCO3), a salt in limestone, plaster, marble, chalk,…
The heater is placed near the floor because the air currents move upwards so the hot air fills up the whole room. Whereas, an air conditioner is placed near the ceiling because the cold breeze tends to settle down. If it is placed near the floor then it will fill just…
The vacuum flask consists of two vessels, one placed within the other and joined at the neck. The gap between the two vessels is partially evacuated of air, creating a partial-vacuum which reduces heat conduction or convection. Heat transfer by thermal radiation may be minimized by silvering flask surfaces…
It could simply be that black paint is cheaper… But I believe that the external coils on the back of refrigerators are painted black for the following reason: There is a rule in nature that says “a color that is better at absorbing heat is also better at radiating heat.” …
We encounter various types of lever in our everyday lives: opening a drink with a bottle opener, cutting paper with scissors, taking the lid off a paint pot using a screwdriver, and – the simplest of all – playing on a seesaw in the park. Yet, the principle of…
A lever is a simple machine consisting of a beam or rigid rod pivoted at a fixed hinge, or fulcrum. A lever is a rigid body capable of rotating on a point on itself. On the basis of the locations of fulcrum, load and effort, the lever is divided…
According to heat definition, it is one of the essential forms of energy for the survival of life on earth. Transfer of heat takes place from one body to another due to difference in temperature as per thermodynamics. We use heat energy for various activities like cooking, ironing, transportation,…
Microorganisms A microorganism, or microbe, is an organism of microscopic size, which may exist in its single-celled form or as a colony of cells. The possible existence of unseen microbial life was suspected from ancient times, such as in Jain scriptures from sixth century BC India. 0
A microorganism is a living thing that is too small to be seen with the naked eye. Examples of microorganisms include bacteria, archaea, algae, protozoa, and microscopic animals such as the dust mite. Microorganisms are found virtually everywhere, except for environments that have been made artificially sterile by humans. Even…
Geometry is, with arithmetic, one of the oldest branches of mathematics. It is concerned with properties of space that are related with distance, shape, size, and relative position of figures. A mathematician who works in the field of geometry is called a geometer. 0
In mathematics, the Fibonacci numbers, commonly denoted Fn, form a sequence, the Fibonacci sequence, in which each number is the sum of the two preceding ones. The sequence commonly starts from 0 and 1, although some authors omit the initial terms and start the sequence from 1 and 1 or…
No single answer to the question “What is light?” satisfies the many contexts in which light is experienced, explored, and exploited. The physicist is interested in the physical properties of light, the artist in an aesthetic appreciation of the visual world. Light or visible light is electromagnetic radiation within the…
The basic arithmetic operations are addition, subtraction, multiplication and division, although arithmetic also includes more advanced operations, such as manipulations of percentages, square roots, exponentiation, logarithmic functions, and even trigonometric functions, in the same vein as logarithms. Arithmetic expressions must be evaluated according to the intended sequence of operations. There…
The cell is the basic structural and functional unit of life. Every cell consists of a cytoplasm enclosed within a membrane, which contains many biomolecules such as proteins and nucleic acids. Cells can acquire specified function and carry out various tasks within the cell such as replication, DNA repair, protein…
A mechanical device that changes the direction or magnitude of a force is known as a simple machine. In general terms, they are defined as simple mechanisms that make use of leverage or mechanical advantage to multiply force. Simple machines have few or no moving parts to modify motion and…
Statistics is the science concerned with developing and studying methods for collecting, analyzing, interpreting and presenting empirical data. Statistics is a highly interdisciplinary field; research in statistics finds applicability in virtually all scientific fields and research questions in the various scientific fields motivate the development of new statistical methods and…
Current Current is the flow of particles in a particular direction. E.g air currents that cause winds or water currents. When particles flow in an electric circuit to produce electricity, it is called an electric current. Electric current The flow of electric charges in a circuit is called an electric…
Plant reproduction is the production of new offspring in plants, which can be accomplished by sexual or asexual reproduction. Sexual reproduction produces offspring by the fusion of gametes, resulting in offspring genetically different from either parent. Asexual reproduction produces new individuals without the fusion of gametes. The resulting clonal plants…
Statistics is simply defined as the study and manipulation of data. As we have already discussed in the introduction that statistics deals with the analysis and computation of numerical data. Let us see more definitions of statistics given by different authors here. According to Merriam-Webster dictionary, statistics is defined as “classified…
If you have looked into the night sky, you may have noticed the Moon appears to change shape each night. Some nights, the Moon might look like a narrow crescent. Other nights, the Moon might look like a bright circle. And on other nights, you might not be able to…
A simple machine is a mechanical device that changes the direction or magnitude of a force. In general, they can be defined as the simplest mechanisms that use mechanical advantage (also called leverage) to multiply force. Usually the term refers to the six classical simple machines that were defined by…
An arithmetic progression or arithmetic sequence is a sequence of numbers such that the difference between the consecutive terms is constant. For instance, the sequence 5, 7, 9, 11, 13, 15, . . . is an arithmetic progression with a common difference of 2. A finite portion of an arithmetic…
Astronomy is one of the oldest natural sciences. The early civilizations in recorded history made methodical observations of the night sky. These include the Babylonians, Greeks, Indians, Egyptians, Chinese, Maya, and many ancient indigenous peoples of the Americas. In the past, astronomy included disciplines as diverse as astrometry, celestial navigation,…
We use numbers in our day to day life. They are often called numerals. Without numbers, we cannot do counting of things, date, time, money, etc. Sometimes these numbers are used for measurement and sometimes they are used for labelling. The properties of numbers make them capable of performing arithmetic…
Heredity is a process in which organisms acquire characteristics from their parents. These characteristics are called traits. Every individual is unique because they have a unique set of traits. The traits which are transmitted by the parent to its offspring during the process of fertilization are inherited traits. This inheritance…
Jupiter is the fifth planet from the Sun and the largest in the Solar System. It is a gas giant with a mass more than two and a half times that of all the other planets in the Solar System combined, but slightly less than one-thousandth the mass of the…
Space and time emerged together 13.787±0.020 billion years ago, and the universe has been expanding ever since. While the spatial size of the entire universe is unknown, the cosmic inflation equation indicates that it must have a minimum diameter of 23 trillion light years, and it is possible to measure…
Sharks are a group of elasmobranch fish characterized by a cartilaginous skeleton, five to seven gill slits on the sides of the head, and pectoral fins that are not fused to the head. Modern sharks are classified within the clade Selachimorpha (or Selachii) and are the sister group to the…
Want your Drawing to be waterproof and float around in water like a ship, Here’s a cool way to do so! 0
Xylem is one of the two types of transport tissue in vascular plants, the other being phloem. The basic function of xylem is to transport water from roots to stems and leaves, but it also transports nutrients. The xylem, vessels and tracheids of the roots, stems and leaves are interconnected…
In earth science, erosion is the action of surface processes (such as water flow or wind) that removes soil, rock, or dissolved material from one location on the Earth’s crust, and then transports it to another location where it is deposited. Erosion is distinct from weathering which involves no movement.…
In botany, a stoma is a pore found in the epidermis of leaves, stems, and other organs, that controls the rate of gas exchange. The pore is bordered by a pair of specialized parenchyma cells known as guard cells that are responsible for regulating the size of the stomatal opening.…
Transpiration is the process of water movement through a plant and its evaporation from aerial parts, such as leaves, stems and flowers. Water is necessary for plants but only a small amount of water taken up by the roots is used for growth and metabolism. Mass flow of liquid water…
Soap molecules consist of a hydrophilic (“water-loving”) end and a hydrophobic (“water-fearing”) end. Water molecules are polar molecules that can dissolve other polar molecules. Fat (and oil) molecules are nonpolar molecules, so they cannot dissolve in water. Milk is a mixture of water, fat, vitamins and minerals. When soap is…
Let’s make our own Glider Plane! A glider is a fixed-wing aircraft that is supported in flight by the dynamic reaction of the air against its lifting surfaces, and whose free flight does not depend on an engine. Most gliders do not have an engine, although motor-gliders have small engines…
Air is a matter of substance, and hence it contains weight and other assets like density and pressure. Generally, the air surrounding us or objects does not show any pressure because it surrounds with equal pressure. In this science activity, we will observe that air shows its pressure when the…
A cloud is an aerosol consisting of a visible mass of minute liquid droplets, frozen crystals, or other particles suspended in the atmosphere of a planetary body or similar space. Water or various other chemicals may compose the droplets and crystals. On Earth, clouds are formed as a result of…
Air is a mixture of many gases. The molecules of gases present in air have weak inter-molecular forces of attraction. Due to this reason these molecules lie far apart from each other i.e. there are large vacant spaces present between these molecules. So, these molecules are free to move in any direction.…