N-N Tutorials

Regelation is defined as the phenomenon in which the ice melts to the water below 0°C on the application of pressure and refreezes back to ice on the removal of pressure. Regelation demonstrates the idea of compressing the ice and turning it into water under pressure and when the pressure is removed, it solidifies again. A few of the examples of regelation are: Glacier acts as a source of a river due to regelation. The mass of the glacier exerts pressure on the lower surface lowering the melting point of the ice at its base. This results in the melting of ice and propels the glacier to slide over the liquid. Under appropriate conditions, liquid water flows from the base of the glacier to lower altitudes when the temperature of the air is above the freezing point of water. Preparation of an ice ball – The ice slab is shredded into pieces, and the shredded pieces are pressurized around the tip of a stick to prepare the ice ball. If two small pieces of ice are taken and pressed against e...

PYTHAGORAS THEOREM  Objective   To verify Pythagoras Theorem by performing an activity. The area of the square constructed on the hypotenuse of a right - angled triangle is equal to the sum of the areas of two squares constructed on other two sides of right angled triangle. Prerequisite Knowledge  In a right angled triangle the square of hypotenuse is equal to the sum of square on the other two sides. Concept of a right-angled triangle. Area of Square = (Side)² Construction of perpendicular lines.  Materials Required  Coloured papers, pair of Scissors, Fevicol, geometry box, sketch pens,  light coloured square sheet. PROCEDURE Take coloured paper draw and cut a right angle triangle ACB right angled at C off side 3cm, 4cm and 5cm as shown in figure 1 Paste this triangle on white sheet of paper.  Draw squares on each side of the triangle on side AB, BC and AC name them accordingly as shown in figure 2. Extend th...