North America has a relatively huge landmass (approximately 24, 709, 000 square kilometers) about 16.5% of the earth’s land area and about 4.8% of its total surface. In this regard, Pacific Time (PT) zone is never enough to be the only time reference. As a result, PDT and PST were introduced. PDT and PST are … Read more
A feedback system is one in which the output signal is sampled and then fed back to the input to form an error signal that drives the system. Feedback systems are very useful and widely used in amplifier circuits, oscillators, process control systems as well as other types of electronic systems. Whereas there are many … Read more
What Are Stationary Waves? Stationary wave also referred to as standing wave is a wave which oscillates in time but whose peak amplitude profiles does not move in space. The peak amplitude of the wave oscillations at any point in space is constant with time, and the oscillations at different points throughout the wave are … Read more
What Is A Pure Substance? A pure substance also referred to as a chemical substance is a material that has a constant composition (is homogenous) and has consistent properties throughout the sample. Pure substances have the potential to form predictable products from chemical reactions. In chemistry, a pure substance consists of only one type of … Read more
Polarity can be described as a separation of charge leading to a molecule or its chemical groups having an electric dipole moment with a negatively charged end and a positively charged end. In other words, bond or the molecular polarities depend upon the electro-negativities of the atoms or the molecules. A molecule is basically said … Read more
Homosporous Pteridophytes Hemosporous life occurs in nearly all bryophytes and in most pteridophytes (lower vascular plants). It is characterized by morphologically identical spores that germinate to produce bisexual (both male and female) gametophytes in pteridophytes but either bisexual or more usually, unisexual (either male or female) gametophytes in bryophytes. Each mature gametophyte bears gametangia (sex … Read more
The classification of organisms is the systematic grouping of living things based on characteristics, hierarchical, or phylogenetic relationships. It is one of the major aspects of taxonomy. Organisms are investigated in terms of their morphology, anatomy, physiology, evolution, behavior, development, and genetics in order to find out relationships between and among them. They are then classified … Read more
Hydrocarbons are compounds that are made up of atoms of carbon and hydrogen exclusively. The unique nature of the carbon ensures that it shares a strong covalent bond with hydrogen. Since carbon atoms will make long chains with relative ease, hydrocarbons can be very big molecules linking even hundreds of atoms. Examples of hydrocarbons include … Read more
What Are Polarized Light? A light wave is an electromagnetic wave that travels through the vacuum of outer space. Light waves are produced by vibrating electric charges. More importantly, light waves are transverse, that is, the vibrating electric vector associated with each wave is perpendicular to the direction of propagation. Polarized light waves are light … Read more
Polar Covalent Bonds Polar covalent bonding is a type of chemical bonding where a pair of electrons is unequally shared between two atoms. In other words, the distribution of electrons around the molecule is no longer balanced. This is due to one of the elements having a higher electronegativity than the other. Atoms with high … Read more