⚡ Quick quiz

Test yourself in under a minute: Class 6 Science Practice Test

From how plants photosynthesize to sorting a mixture by winnowing or sieving, this quiz covers core Class 6 science ideas.

1. 1. What is the name of the process by which green plants make their own food using sunlight and water?

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2. 2. Which essential component of food helps in the growth and repair of our body?

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3. 3. What technique is used to separate husk and heavy seeds of grain using wind or blowing air?

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4. 4. Which joint in the human body operates like a door hinge, bending in only one direction?

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5. 5. Which two terms describe the opposite ends of a magnet where its magnetic force is strongest?

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6. 6. What do we call a root system with one thick main root and smaller side roots branching from it?

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7. 7. What method separates a mixture of solids of different sizes using a mesh screen?

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8. 8. What are the 'three Rs' that help reduce the amount of waste we send to landfills?

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Plant & Animal Structures

Checks plant roots and leaf vein patterns, human bone joints, and the vertebrate/invertebrate split among animals.

1. 1. What do we call the net-like pattern of veins seen on the leaves of most dicot plants?

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   Reticulate venation🔊

   In reticulate venation, the veins spread through the leaf in a net-like pattern. This type of venation is common in dicot plants. Monocot plants like grass and maize instead have parallel venation, where veins run side by side without a network, so checking the vein pattern is a quick way to guess whether a plant is a monocot or dicot without seeing its flower.

2. 2. Which type of joint lets our shoulder move and rotate in many directions?

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   Ball-and-socket joint🔊

   The shoulder is a ball-and-socket joint, which allows movement in many directions, including rotation. This is why the shoulder is more flexible than hinge joints like the elbow, which only bend in one direction, like a door hinge. The hip is the other major ball-and-socket joint in the human body, which is why both the shoulder and hip can rotate a limb through a wide range of motion.

3. 3. What do we call animals that do not have a backbone?

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   Invertebrates🔊

   Animals without a backbone are called invertebrates. This group includes insects, worms, and many sea animals. Invertebrates actually make up the vast majority of known animal species, even though the animals most people think of first (dogs, birds, fish) are vertebrates, which shows how much more common backbone-less body plans are in nature.

Nutrition & Life Processes

Covers dietary fibre, vitamin deficiency diseases, and the basic characteristics that separate living things from non-living objects.

1. 1. What do we call the part of food that gives no nutrients but helps keep our digestive system clean?

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   Roughage (or dietary fibre)🔊

   Roughage, also called dietary fibre, does not give the body nutrients directly, but it helps food move through the digestive tract and keeps digestion healthy. A common misconception is treating roughage like a nutrient the body absorbs. Its real value is bulk: it isn't broken down or absorbed at all, but its presence keeps the intestines moving properly and prevents constipation.

2. 2. Which disease is caused by a long-term lack of Vitamin D in our diet?

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   Rickets🔊

   Vitamin D helps the body use calcium for strong bones. A long-term lack of Vitamin D can cause rickets, which makes bones soft and weak. Unlike most vitamins, the body can make its own Vitamin D from sunlight on the skin, which is why children who spend very little time outdoors are at higher risk even if their diet otherwise seems balanced.

3. 3. Which disease is caused by a lack of iodine in our diet, and causes swelling in the neck?

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   Goitre🔊

   Iodine is needed for the thyroid gland to work properly. A long-term deficiency can make the gland swell, leading to goitre. This is why iodized table salt exists: iodine deficiency was once common in regions far from the sea until salt fortification made it a reliable, everyday source of the mineral.

4. 4. Which vitamin is easily destroyed by heat while cooking food?

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   Vitamin C🔊

   Vitamin C breaks down easily when heated, which is why overcooking vegetables lowers their Vitamin C content. Steaming vegetables briefly, or eating fruits like citrus and amla raw, preserves far more Vitamin C than boiling them for a long time, which is why raw or lightly cooked produce is often recommended specifically for this nutrient.

5. 5. Which basic life process lets plants and animals produce young ones similar to themselves?

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   Reproduction🔊

   Reproduction is the process by which living things produce offspring of their own kind, so their species continues over time. It's a different life process from growth: growth increases an individual's own size, while reproduction creates entirely new individuals, and living things carry out several such life processes together (nutrition, respiration, growth, movement, excretion, and reproduction), not just one.

6. 6. A toy car can roll across the floor, but it is not alive. Name one thing every living thing does that this toy car cannot.

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   Grows, needs food, breathes, or reproduces (any one is correct)🔊

   Movement alone does not make something alive. Living things grow over time, take in food for energy, breathe, and can reproduce, none of which a toy car does on its own. A flickering candle causes the same confusion in reverse: it seems to 'breathe' as it flickers and eventually goes out, but it never grows, feeds, or reproduces, which is why checking several life processes together, not just one, is the reliable test.

Materials, States of Matter & Separation

Tests sorting materials by properties like hardness, natural fibres, separation methods for mixtures, and changes of state in water.

1. 1. Sort these into hard and soft materials: cotton wool, an iron nail, a sponge, a stone.

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   Hard: iron nail, stone. Soft: cotton wool, sponge.🔊

   Hardness is tested by how easily a material changes shape when pressed. An iron nail and a stone keep their shape under pressure, while cotton wool and a sponge squash easily. This property is separate from an object's size or weight, a large piece of cotton wool is still soft and a small iron nail is still hard, so hardness has to be tested by touch rather than guessed from appearance.

2. 2. What fibre do we get from the outer husk of a coconut?

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   Coir🔊

   Coir is the fibre taken from the outer husk of a coconut. It is often used to make ropes, mats, and brushes. Coir fibre naturally resists water damage and rot, which is why it's a popular choice for outdoor mats and ropes that need to survive repeated wetting.

3. 3. What natural fibre is obtained from the stem of the jute plant?

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   Jute🔊

   Jute is a natural plant fibre obtained from the stem of the jute plant. It is commonly used to make sacks, ropes, and bags. Jute is sometimes called the 'golden fibre' because of its natural shine, and India is one of the world's largest producers, particularly in West Bengal, where the warm, humid climate suits the plant.

4. 4. What method separates sand from water by letting the sand settle at the bottom?

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   Sedimentation (followed by decantation)🔊

   In sedimentation, the heavier sand settles at the bottom when left undisturbed in water. The clear water above can then be poured off, which is called decantation. This two-step process is one of the oldest ways to treat muddy river water: letting it settle overnight removes most of the visible dirt before the water is filtered or boiled for drinking.

5. 5. What is it called when ice changes into water on heating?

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   Melting🔊

   Melting is the change of state from solid to liquid caused by heating. Ice melts into liquid water once it warms above 0 degrees Celsius. Melting is a physical change, not a chemical one, so it can be reversed: melted ice can be refrozen into ice again, unlike a chemical change such as burning, which can't be undone by simply cooling the ashes.

6. 6. What is it called when water is heated to 100 degrees Celsius and changes into steam?

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   Boiling🔊

   Boiling is the change of state from liquid to gas that happens throughout the liquid once it reaches its boiling point, 100 degrees Celsius for water. This boiling point isn't fixed everywhere: at high altitudes where air pressure is lower, like in the mountains, water boils at a lower temperature, which is why food can take longer to cook properly there.

7. 7. What do we call it when a liquid slowly changes into a gas, even below its boiling point?

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   Evaporation🔊

   Evaporation happens only at the surface of a liquid and can occur at any temperature, unlike boiling, which needs the liquid to reach its boiling point. This is why wet clothes dry even on a cool day: the water evaporates slowly at room temperature without ever needing to reach 100 degrees Celsius.

8. 8. What do we call the ability of a substance to dissolve in a liquid?

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   Solubility🔊

   Solubility describes how well a substance can dissolve in a liquid, like salt or sugar dissolving in water. Not every solid is soluble, sand and chalk powder stay as visible particles no matter how long they're stirred in water, which is exactly the property that makes sedimentation and filtration possible for separating them.

Motion, Measurement, Light & Shadows

Measures standard units, measuring curved lines, types of motion, and how transparent, translucent, and opaque materials affect light and shadows.

1. 1. Which standard unit do scientists use to measure length, so that measurements match everywhere in the world?

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   Metre🔊

   The metre is the standard unit of length, agreed on so that a measurement taken in one country means the same thing everywhere else. Before standard units existed, people used body-based measures like a hand span or a foot, which varied from person to person, causing real problems in trade and construction whenever two people's 'foot' meant different actual lengths.

2. 2. How can a thread be used to measure the length of a curved line, like the edge of a leaf?

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   Lay the thread carefully along the curve, mark where it ends, then straighten the thread and measure that length with a ruler.🔊

   A ruler alone cannot measure a curve directly, but a flexible thread can follow the curve's shape. Once the thread is straightened out, an ordinary ruler gives its length. This trick works because thread doesn't stretch as it bends around a curve, so the total length of thread used exactly equals the length of the curved path it traced, like the rim of a leaf or a curved road on a map.

3. 3. A car moving straight down a highway shows what type of motion?

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   Rectilinear motion (motion in a straight line)🔊

   Rectilinear motion means movement along a straight path. A car travelling straight down a highway, without turning, is a common example. The moment that same car turns a corner, its motion is no longer purely rectilinear, which is why motion type depends on the actual path taken, not on whether an object is moving fast or slow.

4. 4. The tip of a clock's second hand moving around the clock face shows what type of motion?

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   Circular motion🔊

   Circular motion means movement along the path of a circle. The tip of a clock's second hand always stays the same distance from the centre as it moves, tracing a circle. That fixed distance from the centre is called the radius, and it's the defining feature of circular motion, any point whose distance from a center keeps changing isn't moving in a true circle.

5. 5. A swing moving back and forth again and again shows what type of motion?

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   Periodic motion (oscillatory motion)🔊

   Periodic motion repeats itself after a fixed interval of time. A swing moving back and forth in the same pattern is a common example of periodic, or oscillatory, motion. A pendulum clock's swinging arm and a beating heart are two other everyday examples, since both repeat the same motion after a regular, predictable interval of time.

6. 6. Name a type of material that lets light pass through it clearly enough to see through, like glass.

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   Transparent🔊

   Transparent materials let light pass through them almost completely, which is why objects on the other side of clear glass or water can be seen clearly. This is why windows are made of glass rather than most other solid materials, letting sunlight and a clear view through while still keeping wind and rain out.

7. 7. Name a type of material that does not let any light pass through it at all, like wood.

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   Opaque🔊

   Opaque materials block light completely, so nothing behind them can be seen. Wood, metal, and cardboard are common opaque materials. This complete blocking is exactly why opaque materials are chosen for curtains and walls, where blocking the view (and the light) is the whole point, unlike a window, which needs the opposite property.

8. 8. What do we call a material, like frosted glass, that lets only some light pass through it, without a clear view?

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   Translucent🔊

   Translucent materials let some light pass through, but they scatter it, so shapes on the other side look blurry rather than clear. Frosted glass and butter paper are common examples. This partial blocking is why frosted glass is often used in bathroom windows: it lets daylight in while keeping the outline of whoever is inside impossible to make out clearly.

9. 9. Why does an opaque object standing in front of a light source form a dark shadow?

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   Because the opaque object blocks the light rays completely, leaving a dark area where the light cannot reach.🔊

   A shadow forms in the space directly behind an opaque object, since light rays cannot pass through it. Transparent objects placed in the same spot would not form a dark shadow, since light can pass through them. A translucent object forms a shadow somewhere in between, fainter and less sharply defined than an opaque object's, since only part of the light is blocked.

Electric Circuits & Magnets

Covers electric cells, conductors, switches, and magnet poles and their attraction or repulsion.

1. 1. What part of a torch or a simple circuit stores and supplies the electric energy?

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   Electric cell (battery)🔊

   An electric cell stores chemical energy and converts it into electrical energy, which powers the bulb or other parts connected in the circuit. A cell has two terminals, positive and negative, and current only flows when both are connected in a complete loop, which is why a single broken wire anywhere in the circuit stops the bulb from lighting.

2. 2. What do we call materials that allow electric current to pass through them easily?

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   Conductors🔊

   Materials that allow electric current to pass through them easily are called conductors. Metals like copper and aluminium are common conductors. This is exactly why electrical wires have a metal core coated in plastic or rubber, the metal conducts the current, while the insulating coating stops the current from passing into anything, or anyone, touching the wire.

3. 3. What device is used in a circuit to turn the flow of electric current on or off?

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   Switch🔊

   A switch opens or closes the path of a circuit. Closing it lets current flow, and opening it stops the current. Current needs an unbroken loop to flow, so even the tiny gap created by an open switch is enough to stop the whole circuit, no matter how good a conductor the rest of the wire is.

4. 4. Find the odd one out: Copper, Iron, Aluminum, Plastic.

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   Plastic (it is an insulator, the others are conductors)🔊

   Copper, iron, and aluminium are conductors of electricity. Plastic is an insulator, so it is the odd one out. This is why plug handles and appliance casings are made of plastic rather than metal, an insulator in the right place keeps current from reaching a person's hand even if the wire inside develops a fault.

5. 5. Which pole of a freely hanging bar magnet points toward the Earth's North Pole?

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   North pole🔊

   A freely suspended magnet always lines up in the north-south direction. The end that points toward the geographic North Pole is called the magnet's north pole. This exact behaviour is what makes a compass work, its needle is a small freely suspended magnet, so it always settles pointing north, letting someone find direction even with no landmarks in sight.

6. 6. Which of these is attracted by a magnet: an iron nail or a wooden pencil?

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   The iron nail🔊

   Magnets attract magnetic materials like iron, nickel, and cobalt. Wood is not magnetic, so a wooden pencil is not pulled toward a magnet. Most everyday materials, plastic, paper, glass, and wood, aren't magnetic at all, which is why it's really only a small handful of metals that need to be remembered as the exception rather than the rule.

7. 7. What happens when the north poles of two magnets are brought close together?

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   They repel, or push each other away.🔊

   Like poles, two north poles or two south poles, always repel each other. Only unlike poles pull together. This is easy to feel directly: holding two bar magnets with their north poles facing each other produces a springy push-back force even before the magnets touch, which is the repulsion happening in real time.

8. 8. What happens when the north pole of one magnet is brought close to the south pole of another magnet?

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   They attract, or pull toward each other.🔊

   Unlike poles, a north pole and a south pole, always attract each other. This is the opposite of what happens between two like poles. Together, these two rules, like poles repel and unlike poles attract, are the complete rule for how any two magnets behave, so there's nothing more to memorize beyond these two cases.

Environmental Science

Checks the water cycle, atmospheric composition, biodegradable waste, and everyday waste-reduction practices.

1. 1. What do we call the continuous movement of water between the earth and the atmosphere through evaporation, condensation, and rain?

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   Water cycle🔊

   The water cycle is the continuous movement of water through evaporation, condensation, and precipitation in nature. The sun's heat is what drives the whole cycle: it evaporates water from oceans, rivers, and lakes into vapour, which later cools and condenses into clouds before falling back to Earth as rain, endlessly recycling the same water through the environment.

2. 2. Which gas makes up the largest percentage of the Earth's atmosphere?

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   Nitrogen🔊

   Nitrogen makes up the largest part of Earth's atmosphere, much more than oxygen or other gases. By volume, nitrogen makes up about 78% of the air we breathe, while oxygen, the gas most people assume is most abundant since it's the one our bodies actually use, is only about 21%.

3. 3. What do we call waste that can be broken down naturally by bacteria and other organisms?

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   Biodegradable waste🔊

   Biodegradable waste can be broken down naturally by microorganisms like bacteria and fungi. Vegetable peels and paper are common examples. Non-biodegradable waste, like most plastics, resists this natural breakdown for hundreds of years, which is exactly why separating biodegradable kitchen waste from plastic waste matters for how quickly, or slowly, each ends up decomposing in a landfill.