Our Environment – 5-Page Study Notes Ch-13: Our Environment 🌍 1. Eco-system (पारितंत्र) All the interacting organisms in an area together with the non-living constituents form an Eco-system. किसी क्षेत्र के सभी जीव तथा वातावरण के अजैव कारक संयुक्त रूप से पारितंत्र बनाते हैं। Types: Natural (Forests, Lakes) & Artificial (Gardens, Crop-fields). 2. Components of … Read more
Magnetic Effects of Electric Current – 5-Page Study Notes Ch-12: Magnetic Effects of Electric Current 🧲 1. Introduction (परिचय) Hans Christian Oersted discovered that Electricity & Magnetism are linked. A compass needle is a small bar magnet. Its ends point towards North and South. Magnetic field is a quantity that has both Direction & Magnitude. … Read more
Electricity – 5-Page Study Notes Ch-11: Electricity ⚡ 1. Electric Current (विद्युत धारा) Flow of electric charge in a conductor. आवेश के प्रवाह की दर को विद्युत धारा कहते हैं। Formula: $I = \frac{Q}{t}$ where $Q = ne$ ($n$=no. of $e^-$, $e$=charge on 1 $e^-$). SI Unit: Ampere (A). $1A = 1 C/s$. Measured by: … Read more
The Human Eye – 5-Page Study Notes Ch-10: The Human Eye 👁️ 1. Introduction (परिचय) The Human Eye is like a camera. It forms images on a light-sensitive screen called the Retina. मानव नेत्र एक कैमरे की भाँति है। इसका लेंस निकाय एक प्रकाश-सुग्राही परदे, जिसे रेटिना कहते हैं, पर प्रतिबिंब बनाता है। 2. Main … Read more
Light: Reflection & Refraction – 5-Page Study Notes Ch-9: Light – Reflection & Refraction ✨ 1. Reflection of Light (प्रकाश का परावर्तन) Light travels in straight lines. Laws of Reflection: (i) Angle of incidence $\angle i$ = Angle of reflection $\angle r$. (ii) The incident ray, the normal, and the reflected ray all lie in … Read more
How do Organisms Reproduce – 5-Page Study Notes Ch-7: How do Organisms Reproduce? 🌱 1. Introduction & DNA Copying Reproduction is NOT essential for individual survival but is VITAL for species continuity. DNA Copying: Chromosomes in the nucleus contain DNA (Information source). No biochemical process is 100% accurate $\to$ Variations (विभिन्नता) are created. Why Variation? … Read more
Control and Coordination – 5-Page Study Notes Ch-6: Control & Coordination 🧠 1. Introduction (परिचय) Living organisms respond to environmental changes. Animals: Controlled by Nervous & Muscular tissues. Plants: Controlled by chemical signals (Hormones). Receptors: Specialised tips of nerve cells that detect information (e.g., Gustatory $\to$ Taste, Olfactory $\to$ Smell). 2. The Neuron (तंत्रिका कोशिका) … Read more
Metals and Non-metals – 5-Page Study Notes Ch-3: Metals and Non-metals 🛠️ 1. Physical Properties of Metals Metallic Lustre: Metals have a shining surface in their pure state. Hardness: Generally hard, but varies (Sodium/Potassium can be cut with a knife!). Malleability (आघातवर्ध्यता): Can be beaten into thin sheets (Gold/Silver are best). Ductility (तन्यता): Can be … Read more
Acids, Bases and Salts – 5-Page Study Notes Ch-2: Acids, Bases and Salts 🧪 1. Introduction & Indicators (सूचक) Acids: Sour in taste (खट्टे), turn blue litmus red. Bases: Bitter in taste (कड़वे), turn red litmus blue. Neutralization: Acids and bases nullify each other’s effect. 2. Types of Indicators Natural: Litmus (from Lichen), Turmeric (हल्दी), … Read more
Chemical Reactions and Equations – 5-Page Study Notes Ch-1: Chemical Reactions 🔥 1. Introduction (परिचय) Whenever a chemical change occurs, a chemical reaction has taken place. जब कभी रासायनिक परिवर्तन होता है, हम कह सकते हैं कि एक रासायनिक अभिक्रिया हुई है। Daily life examples: Rusting of iron, Milk turning into curd, Digestion of food. … Read more