THE LEARNING HUB

  PINHOLE CAMERA The pinhole camera is based on the principle that light travels in a straight line. Construction of a Pinhole Camera- To construct a pinhole camera follow the steps described below - Take a small box like a shoebox. Paint the box entirely in black to light-proof it Appropriately determine the distance between the film of plastic or ground glass and light source and make a circular pinhole on the bottom of the box Make a shutter by cutting a piece of thick black chart paper. Use sturdy duct tape to hold the shutter in place Use a light adhesive to control the shutter flap and light entering the box Make a viewfinder out of cardboard. Pinhole Camera Image Characteristics- A real image is obtained as the image is obtained on the screen. The size of the image obtained is comparatively smaller than the actual object. The image is inverted on the x-axis as well as on the y-axis. The image can be used in the analysis of the rectilinear propagation of the light. Uses of...

  Introduction to plants Plants are all around us. They help sustain life on earth by creating food and giving out oxygen that we breathe in. Plants Plants are the immovable living organisms all around us. They are the primary food providers. They are mostly green in colour and use sun as the source of energy to make food. Herbs, shrubs and trees Herbs are the smallest plants and do not have woody stem. Shrubs are slightly larger than herbs. Trees are the largest plants and can have large and thick woody stem. Creepers and climbers Creepers and Climbers are types of plants that need support to grow. Algae and mosses Algae and mosses are the most primitive or simple plants. Algae are found mostly floating on water and mosses are seen on surfaces, rocks or bark of trees in humid conditions.

  Chandragupta Maurya Chandragupta Maurya was the founder of the Mauryan Dynasty/Empire. According to the Brahmanical traditions, he was born of a shudra woman in the Nanda's court. But as the Buddhist tradition, a Kshatriya clan called Mauryas existed in the Gorakpur region. He took the advantage of the decline and weakness of the Nanda's. He overthrew the last ruler of the Nanda dynasty, Dhanananda with the help of Chanakya(Kautilya) and crowned himself as the emperor. North-Western India was under the realm of Seleucus Nicator. Chandragupta Maurya liberated Afghanisthan, Baluchistan and areas to the west of Indus from Seleucus in return of 500 elephants. He brought a vast region under the Mauryan Empire of about 50 lakh square kilometre, which included Bihar, Orissa and Bengal along with the North and North Western part of the Indian Subcontinent. Kerala, Tamil Nadu and parts of North East were the only parts that were not under the Mauryan rule. Chandragupta Maurya was an a...

Ratio and Proportion Ratio  Ratio is the comparison of a quantity concerning another quantity. It is denoted by ":". Two quantities can be compared only if they are in the same unit. Example: Father's age is 75 years and daughter's age is 25                 years.                 Ratio of father's age to daughter's age                 =  F a t h e r ′ s   A g e D a u g h t e r ′ s   A g e = 3 1 = 3 : 1 Golden ratio Two quantities are in golden ratio, if their ratio is same as the ratio of their sum to larger of the two quantities. If two numbers a and b are in golden ratio, then  a + b a = a b . It is approximately equal to 1.618. Difference between fractions and ratios  A fraction describes a part of a whole and its denominator represents the total number of parts. Example:  1 3  means one p...