A series of COLUMNS supporting a large porch is typical of medieval architecture.

A water column of height 30 cm is supporting a 20 cm column of a liquid of density p. Calculate the value of p.

(a) What is reactivity series ? How does the reactivity series of metals help in predicting the relative activities of various metals ? (b) Suggest different chemical processes used for obtaining a metal from its oxides for metals in the middle of the reactivity series and metals towards the top of the reactivity series. Support you answer with one example each.

(a) What is reactivity series of metals ? What can you say about the reactivity of metals which are placed: (i) in the middle of reactivity series? (ii) towards the bottom of reactivity series? (iii) towards the top of reactivity series? (b) A metal is placed in the middle of reactivity series. Suggest a chemical process to obtain this metal from its oxide. Support you answer with one example. (c) A metal is placed towards the top of the reactivity series. Suggest a chemical process to obtain this metal from oxide. Support your answer with one example.

To have large sensitivity in a series LCR circuit

Derive an expression for the rise of liquid in a capillary tube and show that the height of the liquid column supported is inversely proportional to the radius of the tube.