In evolutionary terms can we say that which among bacteria, spider,fish and chimpanzee have a better body design? Why or why not?

A study found that children with light-coloured eyes are likely to have parents with light-coloured eyes. On this basis, can we say anything about whether the light- eye colour trait is dominant or recessive ? Why or why not?

We have read in this chapter that there are four main stakeholders when it comes to forests and wild-life, which among these should have the authority to decide the management of forest produce?Why do you think so?

Colloidal solutions are heterogeneous solutions which contain particles of intermediate size between those of true solutions and suspensions. These particles do not settle under gravity but settle on centrifugation. These particles are found to have charge. We notice many applications of these in our day to day life. Answer the following question : Colloidal medicines are used for intramuscular injections. Why?

Classically, an electron can be in any orbit around the nucleus of an atom. Then what determines the typical atomic size? Why is an atom not, say, thousand times bigger than its typical size? The question had greatly puzzled Bohr before he arrived at his famous model of the atom that you have learnt in the text. To simulate what he might well have done before his discovery, let us play as follows with the basic constants of and see if we can get a quantity with the dimensions of length that is roughly equal to the known of an atom (~ 10^ -10 m).- Construct a quantity with the dimensions of length from the fundamental constants e, m_e , and c. Determine its numerical value.

Electrical resistivities of some substances at 20^@C are given below: Among silver and copper, which one is a better conductor? Why?

classically an electron can be in any orbit around nucleus of an atom. Then what determines the typical atomic size? Why is an atom not, say, thousand times bigger than its typical size? Thequestion had greatly puzzled Bohr before he arrived at his famous model of the atom that you have learnt in the text. To simulate what he might well have done before his discovery, let us play as followswith the basic constants of nature e, me, c and see if we can get a quantity with the dimensions of length that is roughly equal to the known size of an atom (~ 10 m).- You will find that the length obtained above is many orders of magnitude smaller than the atomic dimensions. Further, it involves c. But energies of atoms are mostly in non-relativistic domain where c is not expected to play any role. This is what may have suggested Bohr to discard c and look for else h had already made its appearance elsewhere. Bohr lay in recognising that h, m_e , and e will yield the right atomic size. Construct a quantity with the dimension of length from h, me, and e and confirm that its numerical value has indeed the correct order of magnitude.