Shailesh Koirala 
There are many examples of collisions occurring in our daily life. Some of the examples are: A person walking with his head down may collide with another person walking against him. A car or a vehicle may collide with another car or a vehicle in an accident. The billiard balls collides each other in a … Read more
The constituent particles (atoms or molecules) of a crystal are closely packed and held together by strong mutual force of attraction. This force which exists between different atoms of a crystalline solid is called binding forces. The property of a solid depends upon the nature of the binding forces. There are four types of binding … Read more
Heat energy can be transmitted from one point (or place) to another point (or place) by three different methods. The following are the methods of transmission of heat: conduction, convection and radiation. A) Conduction The process in which heat is transformed from one point to another point in a body by handing over from one … Read more
The charge can stay in the body for some time when the charge is given to that body. The time for which a body can store charge depends on the shape of the body. If the body has pointed ends or sharp edges, the charges leak through them. If the body is round, the charges … Read more
If the junctions of a thermocouple are kept at constant temperature and a current is passed through the wires of the thermocouple, it has been found that one of the junction is heated and the other junction is cooled. That is heat is produced at one junction (junction which is heated) and absorbed at the … Read more
A voltaic cell is an electrochemical cell used to produce electrical energy with the help of a chemical reaction. It is the primary cell which was designated by Alessandro Volta in 1800. Construction A simple construction of a voltaic cell is shown in figure below. It consists of a copper plate and a zinc plate immersed in a … Read more
There are a number of steps involved in extraction of metals from its ores and is itself a science also. The science of extracting metals from their ores and utilizing them for various useful purposes is called metallurgy. The nature and properties of metals make its extraction difficult by using single method. Thus, it is … Read more
Group 13 of the long form of the periodic table consists of five elements: Boron (B), Aluminium (Al), Gallium (Ga), Indium (In) and Thallium (Tl). All these elements collectively are named as boron group elements, because Boron (B) is the first element of this group. These elements form the first group of the p-block elements. … Read more
The reaction rates vary with the concentration of the reactants. The experimental results show that the reaction rates do not always show similar concentration-dependences. In many cases, the rates are found to be proportional to the first power of concentration. There are many reactions in which the rates varied to the second or even third … Read more
A galvanic cell consists of two half-cells. In other words, a galvanic cell consists of two electrodes dipping into the same or two different electrolytes. There are several types of electrodes. Some commonly used electrodes are: a) Metal-Metal ion electrode A metal-metal ion electrode consists of a metal rod or plate dipping into a solution … Read more