Gold Foil Experiment History What is the Gold Foil Experiment? Rutherford’s Gold Foil Experiment Animation Summary With neutrons and protons yet to be discovered, the theory was derived following the classical Newtonian Physics. However, in the absence of experimental proof, this approach lacked proper acceptance by the scientific community. Like the plum pudding model, since the positive charge of atoms was evenly distributed and too small as compared to that of the alpha particles, the deflection of the particulate matter was predicted to be less than a small fraction of a degree....

What are the Types of Motion Translational motion can be rectilinear and curvilinear. In a rectilinear motion, all points move in a straight line. For example, a train moving on its track or a bowling ball rolling down an alley. In a curvilinear motion, all points move in a curved path, For example, a racing car near a turn or a merry-go-round. 2. Rotational Motion In a rotational motion, all points of an object move in a circle....

Generally, water pollution can happen from either point or non-point sources. When contamination originates from a single source, it is called point source pollution. Wastewater discharge into the bodies is an example of such type of pollution. In contrast, non-point source of pollution, like agricultural runoff, occurs from diffuse sources. However, water pollution on Earth is broadly grouped into the following types: 1. Chemical Pollution 2. Surface Water Pollution 3....

All WBCs are nucleated cells that distinguish them from non-nucleated red blood cells (RBCs) and platelets. Normal WBC count is usually between 4 × 109/L and 1.1 × 1010/L, which constitute approximately 1% of the total blood volume, thus about 45% less numerous compared to RBCs. Types of White Blood Cells 1) Neutrophil 2) Eosinophil 3) Basophil 4) Lymphocyte 5) Monocyte Granulocyte: WBCs with granules in their cytoplasm. Granulocytes are of three types: 1) neutrophil, 2) eosinophil, and 3) basophil....

According to the wave-particle duality concept, particles can be described by wavefunctions, which are mathematical functions that represent the probability distribution of finding a particle at different locations. These wavefunctions capture the wave-like behavior of particles. Theories Explaining Wave-Particle Duality Examples Demonstrating Wave-Particle Duality 1. De Broglie Hypothesis Proposed by Louis de Broglie in 1924, this hypothesis suggests that all particles, including matter, have wave-like properties. De Broglie proposed that the wavelength of a particle is inversely proportional to its momentum....

History Explaining the Casimir Effect Static Casimir Effect Dynamical Casimir Effect and Big Bang Theory Zero Point Energy Casimir Effect and Propulsion Applications of the Casimir Effect Drawbacks A very accurate estimation of the force is quite a bit of a challenge as it can be measured only when the distance between the two plates is exceedingly small. With just a slight increase in separation from the submicron level, the effect diminishes rapidly and poses difficulties in measurement....

The word ‘chemotropism’ is an amalgamation of two words, ‘chemo’ and ‘tropism’, referring to ‘chemical’ and ‘tropic movement’, respectively. As it is a type of tropic movement, here also, the growth is directional, i.e., towards or away from an external stimulus. So, parts of the organism respond to the chemical stimulus or gradient, instead of the entire organism. Its Types Examples of Chemotropism Positive chemotropism: Here, the growth occurs towards the stimulus....

What are Enzymes Are All Enzymes Proteins Components Structure: What are They Made of Properties When and How does an Enzyme Work to Catalyze Reactions Factors Affecting Enzyme Activity Types and Examples Functions: Why are Enzymes Important They are found in all living cells that vary in type based on the function it performs. Enzymes help in the process of digestion, blood clotting, and hormone production. Cofactors Some enzymes require a non-protein part for their functioning, known as cofactors....

Unlike the photosynthetic group, there is a parasitic group of Euglena that causes serious blood and tissue diseases such as African sleeping sickness and leishmaniasis in humans. Parts The internal structures found in a typical photosynthetic Euglena are as follows: How do They Move Euglena moves forward and backward (bidirectional movement) using a long whip-like structure called a flagellum that acts like a little motor. The other part that plays a vital role in giving a sense of direction to its movement is the eyespot that helps to detect sunlight and produce food by photosynthesis....

Why Does the Earth have Different Layers and How Are They Formed How Many Layers Does the Earth Have, and What Are They Called All the Earth’s Layers, Their Structure and Composition Crust Upper Mantle Lower Mantle Outer Core Inner Core Thickness: 25 miles (32 km) for continental crust and 3-5 miles (8 km) for oceanic crust Density: ∼ 2830 kg/m3 at the continental crust and ∼ 3000 kg/m3 at the oceanic crust It is the outermost and thinnest layer of our planet and is least dense among all other layers....

1) Renal Corpuscles Also known as Malpighian corpuscle, it is the beginning of the nephron, containing the initial filtering units and is composed of two parts: a) Glomerulus: It is a network or tuft of filtering capillaries enclosed within a cup-shaped pouch called the Bowman’s capsule. It is formed from two types of capillaries called afferent and efferent arterioles. The afferent arteriole brings blood into the glomerulus, while the efferent arteriole collects blood and takes them away from the glomerulus....

These molecules adhere to receptors and enter the cell through the infolding of the plasma membrane, which eventually gets pinched off into a vesicle. Here an essential structural protein, clathrin, coats the budding vesicle giving it its distinctive spherical form. Since RME is a form of endocytosis that helps to ship molecules into the cell from the extracellular matrix through a clathrin-coated vesicle, it is alternatively called Clathrin-mediated endocytosis....

Roots of dicot plants have a taproot system. Carrots, radishes, beets, and parsnips are examples of dicot plants bearing a taproot. However, not all plants possess taproots. Some plants, like grasses, have fibrous roots. Characteristics of Taproots Development of Taproots Functions of Taproots Taproots and Plant Adaptations The primary root continues to elongate and grow vertically downward, becoming thicker and longer. It serves as the central axis of the taproot system....

Examples How is Terminal Velocity Reached Equation Where, C : drag coefficient. It is dimensionless with values depending on the shape of the object. (For example, C = 0.47 for a sphere and C = 0.82 for a long cylinder) ρf : density of the fluid v : object’s velocity A : projected cross-sectional area of the object in a direction perpendicular to the object’s motion. At terminal velocity, v is replaced by vT....

Epithelial cells line the outer surfaces of organs and blood vessels throughout the body and the inner cavities of various internal organs. So, tight junctions are also present in multiple locations. For example, skin, nephron, liver, bile duct, blood-brain-barrier, etc., to name a few. Structure and Formation Functions A few transmembrane proteins (Claudins, Occludins, Junctional adhesion molecules, and Zonula occludens) from each cell membrane form these junctional complexes. They spread from the two adjacent membranes and interlock across the intercellular space....

All food chains start with the producer, which occupies the bottom of the food chain and thus is at the first trophic level. All food chains end with the apex consumer, whose trophic level depends on its prey. For example, it is at the third trophic level if it consumes a primary consumer. If it feeds on a tertiary consumer, it is at the fourth trophic level. The Five Trophic Levels With Examples Trophic Levels and Energy Trophic Levels and Biomass First Trophic Level: Producers All food chains and ecological pyramids start with producers....

Pollution is primarily human-made, but nature can have an adverse effect also sometimes acts as a source of pollution. What are the Different Types of Pollution: Causes and Effects 1. Air Pollution The air in our atmosphere has a roughly stable chemical composition consisting of nitrogen, oxygen, argon, carbon dioxide, and trace amounts of other gases. Any change in the air composition due to the addition of unwanted gases such as sulfur dioxide, carbon monoxide, and nitrogen oxides, chemicals, particulate matter, and biological molecules is called air pollution....

It was the first significant plant hormone to be discovered. In an experiment in the early 1880s, Charles Darwin and his son Francis observed that canary grass coleoptiles bend towards the light source when light is introduced from one direction. Based on the works of Darwin, in 1928, Dutch botanist Fritz Went showed that this bending of light was promoted by a hydrophilic mobile signal which he isolated from an oat coleoptile....

In 1950, Melvin Calvin, James Bassham, and Andrew Benson discovered the Calvin cycle, thus also known as Calvin-Benson-Bassham (CBB) cycle. What Happens In the Calvin Cycle and Where Does It Takes Place in Plants Purpose of the Calvin Cycle Steps The three basic phases of the Calvin cycle are described below: Stage 1: Carbon Fixation It starts when carbon in the form of carbon dioxide enters through minute pores in the leaves called stomata, where they diffuse into the stroma of the chloroplast....

What is the Direction of the Centripetal Force The centripetal force is directed towards the center of curvature of the curved path traced by the object. It is at a right angle to the object’s motion and causes the object to change its direction. How Does the Centripetal Force Affect Circular Motion In a circular motion, the centripetal force is along the radius toward the center. Examples and Applications of Centripetal Force Centripetal Force Equation Difference Between Centripetal and Centrifugal Force Example Problems The force experienced by a car when it makes a turn on a circular road, as shown belowThe Earth’s gravitational force keeps satellites in orbit and causes centripetal motionThe Earth’s gravity is responsible for keeping objects on the surfaceThe tension force on a string swirling a bucket of waterThe force experienced by a roller coaster in an amusement park when going around a loopThe force experienced by a pendulum while swinging...