what are the 7  characteristics of a living organism ?

what is the use and where do we use frictional force, magnetic force and gravity? what all forces are getting cancelled when a ball is laying still in the ground ?

why, i thought red is hot

what is light year? explain no (4) .

1. HomeostasisKeeps the body stable and alive. 2. GrowthMore cells = growth; new abilities = development. 3. CellsOrganized cells keep organisms working. 4. AdaptationChanges help survival. 5. Cell Types* Prokaryotic: Simple, no nucleus. * Eukaryotic: Complex, has nucleus.

1. Forces in SublimationWeak forces let solids turn directly to gas. 2. Uses* Freeze-Drying: Preserves food/medicine. * Purification: Separates pure substances. 3. Pros/ConsPros: Clean, preserves sensitive items.Cons: Expensive, needs equipment. 4. Lab DemoUse dry ice or heat iodine to see sublimation. 5. In NatureIce/snow turns to vapor in dry, cold places. 6. MeasuringWeight loss shows how fast sublimation happens.

* Volatile Substances: * Alcohol, gasoline, perfume, acetone. * Removing Impurities: * Filtration, distillation, recrystallization. * Impact of Impurities: * Changes melting/boiling points, strength, and reactivity. * Impurities & Phase Transitions: * Lower freezing point, raise boiling point. * Measuring Volatility: * Vapor pressure and boiling point. * Impurities & Conductivity: * Lower electrical and thermal conductivity.

1. Freezing vs. Melting: * Freezing: Liquid → Solid (loses energy). * Melting: Solid → Liquid (gains energy). 2. Vaporization vs. Evaporation: * Vaporization: Liquid → Gas (boiling). * Evaporation: Surface → Gas (no boiling). 3. Condensation: * Gas → Liquid (cooling, e.g., dew). 4. Sublimation: * Solid → Gas (e.g., dry ice). 5. Pressure's Role: * High pressure = solid/liquid. * Low pressure = gas. 6. Energy in Transitions: * Add energy = melt/boil. * Lose energy = freeze/condense. 7. Thermodynamics: * Energy moves but doesn’t disappear.

* Particles in gases: Move fast, randomly, and spread out. * Kinetic energy: Energy of motion; more temp = faster particles. * Intermolecular forces: Strong in solids, weak in liquids, almost none in gases. * Phase transitions: Particles gain/lose energy; bonds break/make. * Temperature: High temp = faster movement. * Pressure: High pressure = particles closer; low pressure = spread out.

* How do hydroelectric plants work?Water spins turbines that generate electricity. * Benefits and challenges of water energy?Benefits: Renewable, efficient, reliable.Challenges: High cost, environmental impact, location limits. * How does efficiency vary?Efficiency depends on water flow and environmental factors. * Environmental impacts of dams?Dams disrupt ecosystems, flood land, affect water quality. * How is water energy integrated?Connected to the grid, balances renewable energy, uses pumped storage. * Innovative applications?Small hydropower, tidal/wave energy, hydro desalination. * Government influence?Subsidies, tax credits, regulations, and research funding support water energy

1. Efficiency: Best at steady winds (12–25 m/s). 2. Impacts: * Positive: No pollution, cuts emissions. * Negative: Wildlife and noise issues. 3. Power Grid: Batteries, smart grids, and backups help. 4. Uses: Home turbines, wind-powered ships, off-grid power. 5. Policies: Subsidies, tax credits, and renewable energy laws. 6. Future: Bigger turbines, floating farms, hybrids with solar. 7. Offshore vs. Onshore: Offshore = efficient but costly; onshore = cheaper.

1. Height and Gravitational Potential EnergyHigher height = more gravitational potential energy (PE=mghPE = mghPE=mgh). 2. Elastic Potential EnergyStored in stretched or compressed objects like springs or rubber bands. Released as motion. 3. Chemical Potential EnergyEnergy in bonds, like in batteries (power devices) or food (gives us energy). 4. Potential Energy and WorkWork done on an object (lifting, stretching) increases its potential energy. 5. Potential Energy in Fields * Gravitational: Higher = more energy. * Electric: Position near charges changes energy. 6. Real-Life Examples * A roller coaster (gravitational). * A slingshot (elastic). * Food and fuel (chemical).

* Wind to Electricity: * Wind spins blades → Generator turns motion into electricity. * Environmental Benefits: * No pollution and renewable. * Wind Farms in Rural Areas: * Power supply, jobs, and cleaner air. * Wind vs. Solar: * Wind needs space; solar fits rooftops, ideal for cities. * Energy Calculation: * Formula: P=0.5×1.225×5026.5×123×0.45

* Rock’s Potential Energy:PE=m×g×h=5×9.8×10=490PE = m \times g \times h = 5 \times 9.8 \times 10 = 490PE=m×g×h=5×9.8×10=490 J * Answer: 490 J * Energy Increase of Object:ΔPE=m×g×Δh=2×9.8×4=78.4\Delta PE = m \times g \times \Delta h = 2 \times 9.8 \times 4 = 78.4ΔPE=m×g×Δh=2×9.8×4=78.4 J * Answer: 78.4 J * Book’s Height:h=PEm×g=29.41.5×9.8=2h = \frac{PE}{m \times g} = \frac{29.4}{1.5 \times 9.8} = 2h=m×gPE​=1.5×9.829.4​=2 meters * Answer: 2 m * Rubber Band: * When released, stored energy becomes motion energy. * Food Energy: * Chemical energy in food turns into energy for our body when digested.

1. Movement: Animals move actively (e.g., cheetahs run). Plants grow toward light. 2. Respiration: Without oxygen, animals can’t make energy, leading to weakness or death. 3. Sensitivity: Rabbits sense predators and escape quickly, improving survival. 4. Nutrition: Lions need protein to grow strong; plants need sunlight and minerals. 5. Excretion: Animals remove CO₂ and urea; plants release oxygen and shed leaves. 6. Reproduction: Drought or harsh winters can reduce offspring. Reproduction keeps species going. 7. Response to Danger: Deer sense predators, then the nervous and muscular systems help them flee.

1. Diet: Eat sap, nectar, tree gum, and insects in the wild. 2. Communication: Bark, hiss, and use scent marking to bond. 3. Social Behavior: Live in colonies; groom each other for bonding. 4. Reproduction: Joeys stay in mom’s pouch for about 2 months. 5. Health in Captivity: Need a balanced diet and social interaction to avoid stress and health issues. 6. Habitat: Large, tall cages with branches, toys, and hiding spots keep them happy. A natural, engaging environment is key!

1. Soil Components: Minerals, organic matter, air, water, and microbes—essential for fertility. 2. Soil Organisms: Bacteria and earthworms improve nutrient availability and structure. 3. Erosion: Causes nutrient loss; prevent with cover crops and terraces. 4. pH: Affects nutrient access; ideal range is 6-7. 5. Conservation: Crop rotation, reduced tillage, composting keep soil healthy. 6. Human Impact: Deforestation and urbanization reduce soil quality. 7. Testing: Field and lab tests check texture, nutrients, pH. Healthy soil = productive plants!

* Potential and Kinetic Energy: * Energy shifts between potential (stored) and kinetic (motion) without being lost—just changes form, like a roller coaster going up and down. * Renewable Energy: * Solar panels and wind turbines capture energy from nature, transforming it without using up resources, thanks to conservation of energy. * Efficient Machine Design: * Knowing energy conservation helps engineers design machines that waste less energy, like hybrid cars that reuse braking energy. * Environmental Impact: * Using energy wisely helps reduce waste, pollution, and conserves resources for sustainability. * Energy Transformations: * Energy changes form but never disappears, like electrical energy becoming light without any energy loss. * Common Misconceptions: * Misconception: Energy is "used up." * Truth: It’s not used up; it just changes form!

1. Examples: * High viscosity: Honey, syrup (thick, slow). * Low viscosity: Water, alcohol (thin, fast). 2. Molecules and Viscosity: * Bigger, complex molecules make a liquid thicker (higher viscosity). 3. Viscosity in Industry: * Lubrication needs thicker oils. Pipes work better with thin, fast-flowing liquids. 4. Additives and Impurities: * Additives or impurities can make a liquid thicker or thinner. 5. Changing Viscosity: * Heating makes it thinner; cooling makes it thicker. Chemicals can also adjust it. 6. Dynamic vs. Kinematic Viscosity: * Dynamic: Measures thickness when force is applied. * Kinematic: Measures how fast it flows by gravity.

1. Open Circuit: * If the circuit is open (broken), electricity stops, and parts don’t work. 2. Switches: * Switches open (OFF) or close (ON) circuits to control flow. 3. Safety: * Closed circuits have electricity flowing (risk of shock). Open circuits are safer. 4. Troubleshooting: * Use a tester: if current flows, it’s closed; if not, it’s open. 5. Examples: * Light bulbs, computers, and phones all need closed circuits to work. 4o