To emit an electron from the metal surface the photon needs energy which is equal to the sum of the kinetic energy of electrons and energy needed... View Article
The photoelectric effect is the phenomenon of the emission of electrons from the metal surface when electromagnetic radiation of suitable... View Article
1 eV is defined as the energy gained by an electron when it has been accelerated by a potential difference of 1 volt, hence 1 eV = 1.60210-19J.... View Article
We know that metal has free electrons (negatively charged particles) in its surface. But free electrons cannot escape from the metal surface... View Article
Answer: Odometer, or odograph, is a device that measures the distance travelled by an automobile based on the perimeter of the wheel as the... View Article
Answer: An earthquake is the shaking of the surface of Earth due to the sudden release of energy in the Earth’s crust, as a result, seismic... View Article
Lactometer is a small glass instrument that is used to test the purity of the milk. It works on the principle of specific gravity of milk... View Article
Answer: Fullerenes One of the most influential elements we see around us is a carbon (C) with atomic number 6. Carbon is one of the elements... View Article
The imaginary line that separates light from the darkness and day from the night is known as the circle of illumination. Earth’s axis refers to... View Article
Sound waves are mechanical waves because they need a material medium for propagation, like air or liquids like water or metals like silver. The... View Article
Answer: Metals are an excellent conductor of electricity and heat because the atoms in the metals form a matrix through which outer electrons... View Article
Sodium is the metal stored in kerosene oil in order to prevent it from coming in contact with oxygen and moisture. Sodium is a highly reactive... View Article
In a series connection, the current flowing through all the components of the circuit is the same. Ammeter aims at measuring the current in the... View Article
Friction is a force that resists the relative motion between two objects or materials. The causes of the resistive force of friction are:... View Article
The amount of friction that can be applied between two surfaces is limited and if the forces acting on the body are made sufficiently great, the... View Article
Retardation is nothing but a negative acceleration. The velocity of the body may either increase or decrease. The change in velocity is known as... View Article
The three major components of biodiversity are: Genetic diversity - It refers to the diversity exhibited by a single species at the genetic... View Article
Amoebiasis is an infectious disease that is caused by the Entamoeba group. The main source of contamination for amoebiasis is physical contact... View Article
Haemozoin or hemozoin is formed by blood-feeding parasites as the end product of their digestion. It is usually formed by the digestion of blood.... View Article
Cyclosporin is an immunosuppressant drug which is typically administered by mouth. It can also be injected intravenously or as eye drops.... View Article