natural numbers

Find the sum of all the natural numbers between 1 and 200, which are multiples of 2. => 10080 or 20200 or 10100 or 10120..

Find the arithmetic mean of the first n natural numbers. => n + 1 2 or n ( n + 1 ) 2 or n ( n + 1 ) ( 2 n + 1 ) 6 or n ( n + 1 ) 2 4..

Beetles with brown genes escaped predation as their colour became one with the environment and they remained as if hidden. In the process they survived to reproduce more frequently than beetles with green genes. This allowed more brown genes to go into the next generation. In another situation an ..

Sound is a form of energy. It is produced by the vibration of particles and it travels in a wave-like motion. The number of waves passing a point per second is called the frequency and its unit is Hertz (Hz). The pitch of the sound (high or low sounding) is measured by the frequency. Man..

Due to its tetravalent nature carbon always form covalent bonds by sharing electrons with one, two, three or four carbon atoms or atoms of other elements or groups of atoms as discussed earlier. The tetra covalency of carbon atom allows it to combine easily with other carbon atoms to ..

The formula S = [n(n+1)] 2 is used to find the sum of the first n natural numbers. Find the sum of the first 18 natural numbers. => 171 or 162 or 189 or 180..

Occurrence of Elements in Nature - A large number of elements occur inside or around the earth. Less reactive elements, like platinum, gold, nitrogen, oxygen etc., occur in free (native) state. Chemically active elements always occur in the combined state i.e. in the form of com..

Although organic compounds are basically made up of carbon, hydrogen, oxygen and a few more elements, their number is far greater than the inorganic compounds which don't form bonds. At present almost five million organic compounds are known to use more than the elements of all the compo..

According to wave theory when light falls on a metal surface, energy is continuously distributed over the surface. All the free electrons receive light energy and when the energy received exceeds that of work function, an electron may escape the surface. If we user a low intensity source, it may ta..

General Characteristics of Natural Radioactivity - It is a nuclear phenomenon. It is due to the instability of the nucleus. It is a spontaneous, continuous and irreversible process. It is independent of external factors such as pressure, temperature, state of substance, electrical field, ..