1. Radio waves are
<p>Radio waves are <strong>electromagnetic waves</strong>. They are a type of electromagnetic radiation with wavelengths in the electromagnetic spectrum ranging from about one millimeter to 100 kilometers, and they are used in various communication technologies, including radio, television, and wireless networks.</p>
2. Units of focal power
<p>The unit of focal power is <strong>Dioptre</strong>. It is defined as the reciprocal of the focal length measured in meters. A lens with a focal length of 1 meter has a focal power of 1 dioptre.</p>
3. Bending of light rays around the smaller obstacles is called
<p>The bending of light rays around smaller obstacles is called <strong>Di fraction</strong>. Diffraction occurs when light encounters an obstacle or a slit that is comparable in size to its wavelength, causing the light to spread out and bend around the edges.</p>
4. Sun glasses works on the principle
<p>Sunglasses work on the principle of <strong>polarization of light</strong>.</p>
<p>They are designed to reduce glare from surfaces like water or roads by blocking certain orientations of light waves, which helps improve visibility and reduce eye strain.</p>
5. Magnitude of diffraction of light is depends on
<p>The magnitude of diffraction of light depends on <strong>all the above</strong> factors:</p>
<ol>
<li><strong>Size of the obstacle</strong>: Smaller obstacles relative to the wavelength of light cause more significant diffraction.</li>
<li><strong>Wavelength of the light wave</strong>: Longer wavelengths diffract more than shorter wavelengths.</li>
<li><strong>Angle of the beam of the light ray</strong>: The angle at which light strikes an obstacle can also influence the diffraction pattern.</li>
</ol>
<p>Therefore, all these factors play a role in the diffraction of light.</p>
6. Which rays are used to night vision
<p><strong>Infrared rays</strong> are used for night vision. Night vision devices often utilize infrared technology to detect heat emitted by objects, allowing them to create images in low-light or dark conditions. X-rays and gamma rays are not typically used for night vision applications.</p>
7. To detect fake notes, we use
<p>To detect fake notes, we use <strong>UV rays</strong> (ultraviolet rays). Many currencies have features that are only visible under UV light, such as watermarks and security threads, which help in identifying counterfeit bills.</p>
8. Which lens used to see minute particles of ears,nose and throat( ENT Doctor)
<p>ENT doctors use <strong>microscope lenses</strong> to see minute particles in the ears, nose, and throat. Microscopes provide the necessary magnification and clarity to examine small structures in these areas effectively.</p>
<p>While <strong>convex lenses</strong> can be used for magnification, the specialized equipment for ENT examinations typically involves microscopes.</p>
9. To preserve food for long duration, __________ is used
<p>To preserve food for a long duration, <strong>Sodium Benzoate</strong> is widely used as a food preservative. It prevents the growth of bacteria, yeast, and molds in acidic foods and beverages, extending shelf life. While <strong>Sodium Chloride</strong> (salt) is also used, Sodium Benzoate is more effective in various applications.</p>
10. Herbs, Trees and Shrubs are the one of the following?
<p>Herbs, trees, and shrubs are categories of plants distinguished by their physical characteristics. Herbs are typically non-woody and often used for culinary or medicinal purposes.</p>
<p>Trees have a single, woody trunk and can grow tall, while shrubs are shorter, woody plants with multiple stems, commonly used in landscaping and gardens.</p>
11. Plants which takes support and grow upwards are called as?
<p>Climbers are plants that need support to grow vertically. They use structures like trellises, fences, or other plants to climb and access sunlight.</p>
<p>Common examples include vines such as ivy and morning glory. This growth habit allows them to thrive in various environments, maximizing their exposure to light and air.</p>
12. Plants with weak stems that cannot grow upright but can spread on the ground are called?
<p><strong>Creepers</strong> have weak stems that cannot support themselves, so they spread along the ground. Examples include plants like groundcovers and certain types of strawberries.</p>
13. Plants with green and tender stems are called as?
<p><strong>Herbs</strong> are plants with green, tender stems that are non-woody. They are commonly used in cooking, medicine, and aromatherapy, and often include varieties like basil, parsley, and mint.</p>
14. One of the following item comes under Shrub Category of plants?
<p><strong>Lemon</strong> plants are shrubs due to their bushy, multi-stemmed growth and small to medium size.</p>
<p>Unlike trees, they don't grow tall and have woody stems, fitting the shrub category of plants.</p>
15. Mango comes under which category of plant?
<p>Mango is classified as a tree due to its large size, woody stem, and ability to grow up to 30-40 meters tall, making it distinct from shrubs and herbs.</p>
16. Tomato comes under which category of plants?
<p><strong>Tomato plants</strong> are classified as<strong> herbs</strong> because they have soft, non-woody stems and are relatively short-lived, making them different from shrubs and trees.</p>
17. Which Material expands on heating?
<p><strong>Iron</strong> expands when heated because the increase in temperature causes its atoms to vibrate more, increasing the space between them, leading to thermal expansion typical of metals.</p>
18. Process of conversion of vapour into liquid form is called as?
<p><strong>Condensation </strong>is the process of converting vapor into liquid form, typically when gas cools down and loses energy, allowing molecules to come closer together to form a liquid.</p>
19. Evaporation means?
<p>Evaporation is the process of converting liquid water into vapor, typically at the surface, when heat causes water molecules to gain energy and escape into the air as gas.</p>
20. After Sedimentation water is removed along with dust, this process is known as?
<p>After sedimentation, decantation is the process of carefully pouring off the clear liquid from the settled solids, effectively separating the water from dust and other particulate matter.</p>
21. The heavier component in a mixture settles down when water is added to the mixture, this process is called as?
<p><strong>Sedimentation</strong> is the process where heavier components in a mixture settle down at the bottom when water or another liquid is added, allowing for separation from the lighter components.</p>
22. Pebbles and stones are removed from sand by the process of?
<p><strong>Pebbles and stones</strong> are removed from sand through <strong>sieving</strong>, a process that uses a mesh or screen to separate larger particles from finer materials, ensuring a cleaner, finer sand.</p>
23. The method of separating components from a mixture is called?
<p><strong>Winnowing</strong> is a method used to separate lighter components from heavier ones in a mixture, typically involving grains. This process utilizes wind or air currents to blow away the lighter chaff, leaving the heavier grains behind. It is commonly used in agriculture for cleaning harvested grains, ensuring the removal of husks and debris.</p>
<h3>Points are:</h3>
<ul>
<li><strong>Process:</strong> Uses air currents to separate lighter materials from heavier ones.</li>
<li><strong>Common Use:</strong> Primarily used in agriculture for grain cleaning.</li>
<li><strong>Example:</strong> After harvesting, farmers toss the mixture into the air; the wind carries away the lighter chaff, while the heavier grains fall back down.</li>
</ul>
24. The process by which we separate grain from stalks is known as?
<p><strong>Threshing</strong> is the process used to separate grains from their stalks or husks, typically involving mechanical means or manual methods to detach the edible part from the inedible parts</p>
25. Tumbler is made up of?
<p><strong>Tumblers</strong> are designed to hold liquids, so they are typically made from materials that can contain water without leaking, such as glass, plastic, or metal.</p>
<p>Cloth would not be suitable because it is porous and cannot hold liquids</p>
26. The materials through which the object can be seen but not clearly are known as?
<p><strong>Translucent</strong> materials allow light to pass through but scatter it, making objects on the other side visible but not clear. Examples include frosted glass and wax paper.</p>
27. Jute is mainly grown in which region?
<p>Jute is indeed mainly cultivated in the eastern and northeastern regions of India, with <strong>West Bengal</strong> being the largest producer, contributing significantly to the country’s overall jute production. Assam, Bihar, Odisha, Tripura, and Uttar Pradesh also play important roles in jute cultivation. Jute thrives in the warm, humid climate of these regions, making it suitable for large-scale farming.</p>
28. Fibers which are not obtained from plant or animal sources are called as?
<p><strong>Synthetic fibers</strong> are those that are not derived from natural plant or animal sources but are instead made through chemical processes, such as nylon, polyester, and acrylic.</p>
29. Fibers obtained from plants and animals are called?
<p><strong>Natural fibers</strong> are those derived from plant (such as cotton, jute, and linen) or animal sources (such as wool, silk, and alpaca).</p>
30. Iron deficiency may cause?
<p>Iron deficiency can lead to <strong>anemia</strong>, a condition where the body lacks enough healthy red blood cells due to insufficient iron, resulting in fatigue and weakness.</p>
31. Which of the following are the symptoms of anemia?
<p><strong>Anemia symptoms</strong> include <strong>headaches, weakness, and hairfall.</strong> Headaches occur due to reduced oxygen supply to the brain, while weakness arises from insufficient red blood cells to transport oxygen throughout the body. Hairfall can result from nutrient deficiencies associated with anemia. Recognizing these symptoms is essential for timely diagnosis and treatment.</p>
32. Iodine deficiency causes?
<p>Iodine deficiency causes <strong>goiter</strong>, an enlargement of the thyroid gland. Insufficient iodine affects thyroid hormone production, leading to this condition, which can result in various metabolic and developmental issues.</p>
33. Vitamin D deficiency may cause?
<p><strong>Vitamin D</strong> deficiency can lead to<strong> rickets</strong>, a condition characterized by the softening and weakening of bones in children, primarily due to inadequate calcium and phosphate absorption.</p>
34. Vitamin C deficiency may cause?
<p><strong>Vitamin C</strong> deficiency can cause <strong>scurvy</strong>, a condition characterized by symptoms such as fatigue, swollen gums, joint pain, and anemia due to its essential role in collagen production and overall immune function.</p>
35. Vitamin A deficiency may cause?
<p><strong>Vitamin A</strong> deficiency can lead to <strong>loss of vision</strong>, particularly night blindness and, in severe cases, complete blindness, as vitamin A is essential for maintaining healthy vision and eye function.</p>
36. Diseases that may occur in deficiency of nutrients are called?
<p><strong>Diseases</strong> caused by a lack of essential nutrients, vitamins, or minerals in the diet are known as <strong>deficiency diseases</strong>. Examples include scurvy (vitamin C deficiency) and rickets (vitamin D deficiency).</p>
37. A person may be getting enough food to eat, but sometimes the food may not contain a particular nutrient. If this continues over a long period of time, the person may suffer from the following?
<p>If a person consumes enough food but lacks specific nutrients, they may suffer from nutrient deficiencies over time, leading to various health issues.</p>
38. Too much of intake of fatty foods result in?
<p>Excessive intake of fatty foods can lead to weight gain and obesity, as these foods are often high in calories and can contribute to an imbalance in energy intake and expenditure.</p>
39. Which of the following vitamin is lost while heating and cooking?
<p><strong>Vitamin C</strong> is sensitive to heat and can be lost during cooking and heating processes, making it important to handle and prepare foods carefully to retain this nutrient.</p>
40. Balanced diet is defined as?
<p>A balanced diet is defined as consuming the right amounts of nutrients required for the body’s optimal functioning. It includes carbohydrates, proteins, fats, vitamins, and minerals in appropriate proportions.</p>
41. Which the following helps us to absorb nutrients from food?
<p><strong>Water </strong>is essential for various bodily functions, including the absorption of nutrients from food, as it helps dissolve vitamins and minerals, facilitating their uptake in the digestive system.</p>
42. Source of Calcium?
<p>While eggs contain some calcium, other significant sources include dairy products (like milk and cheese), leafy greens, and fortified foods. However, among the options listed, eggs are the most relevant source.</p>
43. Which of the following does not provide nutrients to our body?
<p>Roughage, or dietary fiber, does not provide nutrients in terms of calories or essential vitamins and minerals. However, it is essential for digestive health. Carrots and milk provide vital nutrients.</p>
44. Dietary fibers are also known as?
<p>Dietary fibers are commonly referred to as roughage, as they are the indigestible parts of plant foods that aid in digestion and promote bowel health.</p>
45. Source of Iron?
<p>Iron-rich foods typically include:</p>
<ul>
<li>Red meat</li>
<li>Poultry</li>
<li>Fish</li>
<li>Lentils</li>
<li>Beans</li>
<li>Tofu</li>
<li>Spinach</li>
</ul>
46. Source of iodine?
<p>While papaya contains some iodine, the best sources of iodine are typically seafood (like fish and seaweed), dairy products, and iodized salt. Among the options given, papaya is the most relevant.</p>
47. In presence of sun, our body itself prepares?
<p>In the presence of sunlight, specifically <strong>ultraviolet B (UVB) rays</strong>, our body synthesizes <strong>vitamin D</strong> through a process that occurs in the skin.</p>
48. Proteins are often called as?
<p>Proteins are often referred to as body-building foods because they are essential for growth, repair, and maintenance of body tissues, including muscles.</p>
49. Which of the following vitamin helps our body to use calcium for bones?
<p>Vitamin D is crucial for the body's ability to absorb calcium, which is essential for maintaining strong bones and overall bone health.</p>
50. Which of following vitamin makes our body to fight against diseases?
<p><strong>Vitamin D</strong> is crucial for the body's ability to absorb calcium, which is essential for maintaining strong bones and overall bone health.</p>
51. Which of the following vitamin keeps our eyes and skin healthy?
<p><strong>Vitamin A</strong> is essential for maintaining healthy vision, skin, and immune function. It plays a key role in the maintenance of epithelial tissues and helps prevent vision-related issues.</p>
52. Which of the following food item contains starch?
<p>Potatoes are rich in starch, which is a complex carbohydrate that serves as a significant energy source. Other starchy foods include rice, corn, and bread.</p>
53. Presence of Starch can be indicated by the following color?
<p>The presence of starch can be indicated by a blue-black color when iodine solution is applied to a starch-containing sample.</p>
54. Which of the following nutrients are present in our body?
<p>Both carbohydrates and water are nutrients present in our body. Carbohydrates serve as a primary energy source, while water is essential for various physiological functions, including hydration, digestion, and temperature regulation.</p>
55. Components that are needed to our body, those are?
<p><strong>Nutrients</strong> are the components needed by our body for energy, growth, maintenance, and overall health. They include carbohydrates, proteins, fats, vitamins, minerals, and water.</p>
56. Item of grain for Punjab region is?
<p>"<strong>Makki</strong>," which refers to maize or corn, is also cultivated in Punjab, particularly as a crop for fodder and food. However, <strong>wheat</strong> is the primary grain associated with the Punjab region, as it is a major staple crop and central to the agriculture and economy of the area.</p>
57. Animals which eat only both plants and animals are called?
<p><strong>Omnivores</strong> are animals that consume both plants and animals as part of their diet. Examples include humans, bears, and pigs.</p>
58. Lion comes under which category?
<p>Lions are classified as carnivores because they primarily eat meat, hunting and feeding on other animals for their sustenance.</p>
59. Animals which eat only plants are called?
<p><strong>Herbivores</strong> are animals that primarily consume plants. Examples include cows, sheep, and rabbits.</p>
60. Electric cell stops working if one of the following occur?
<p>This is because the chemical reactions that produce electricity in the cell eventually deplete the reactants. While the other options can affect performance, the primary reason a cell ceases to function is the exhaustion of its chemicals.</p>
61. _______ is a conductor of Electricity?
<p><strong>Iron</strong> is a metal and a good conductor of electricity due to its free electrons, which allow electric current to flow easily. In contrast, plastic, paper, and wood are insulators.</p>
62. The materials which are attracted by the magnet are called as?
<p><strong>Magnetic materials</strong>, like iron, cobalt, and nickel, are attracted to magnets due to their atomic structure, which allows them to align with magnetic fields and exhibit magnetism.</p>
63. Fats,vitamins,proteins and minerals are components of food are necessary for our body are known as
<p><strong>Nutrients</strong> are essential components of food, including fats, vitamins, proteins, and minerals. They support growth, energy production, immune function, and overall health, playing vital roles in bodily processes.</p>
64. Wool is obtained from the ______ of sheep or yak ?
<p><strong>Wool</strong> is derived from the fleece of sheep or yak, which is the thick coat of hair that protects these animals from harsh weather.</p>
<p>The fleece is sheared, cleaned, and processed to create various woolen products. Wool is valued for its warmth, durability, and ability to wick moisture, making it ideal for clothing.</p>
65. Certain type of objects are used to test whether a substance is base or acid,such substance is known as?
<p>An <strong>indicator</strong> is a substance that changes color when added to acidic or basic solutions, helping determine their pH. Common examples include litmus paper, phenolphthalein, and methyl orange.</p>
66. ______ number of hydrogen molecules are present in water?
<p>Water (Hâ‚‚O) consists of two hydrogen (H) atoms and one oxygen (O) atom. Therefore, two hydrogen molecules are present in each water molecule.</p>
67. The process of getting back the water which is evaporated is called as?
<p>The <strong>water cycle</strong> (or<strong> hydrological cycle</strong>) involves the continuous process of evaporation, condensation, and precipitation, through which water is cycled back to the Earth after evaporation.</p>
68. Smoke contain ___?
<p>Smoke contains both <strong>oxygen</strong> and <strong>carbon dioxide</strong> along with other gases and particulate matter, as it results from the incomplete combustion of substances.</p>
69. Water contains ___?
<p><strong>Water (Hâ‚‚O)</strong> is made of two hydrogen atoms and one oxygen atom. The hydrogen atoms are bonded to the oxygen atom at an angle of 104.45°. Water is essential for life and exists in <strong>gaseous</strong>, liquid, and solid states.</p>
70. Carbon monoxide reacts with oxygen to generate the below?
<p>When <strong>carbon monoxide (CO)</strong> reacts with oxygen (Oâ‚‚), it forms <strong>carbon dioxide (COâ‚‚)</strong> through the chemical reaction: <span class="katex"><span class="katex-mathml">2CO+O2→2CO22CO + Oâ‚‚ → 2COâ‚‚</span><span class="katex-html" aria-hidden="true"><span class="base"><span class="mord"><span class="msupsub"><span class="vlist-t vlist-t2"><span class="vlist-r"><span class="vlist-s">​</span></span></span></span></span></span></span></span></p>
71. The evaporated water is get back to the ground by _____?
<p>The evaporated water returns to the ground primarily through <strong>rain</strong> as part of the water cycle. While the sun facilitates evaporation, it does not directly bring the water back to the ground.</p>
72. _____ is an example for indicator?
<p><strong>Litmus</strong> is a natural indicator used to determine acidity or alkalinity in solutions. It changes color: red in acidic solutions and blue in basic solutions, helping identify pH levels.</p>
73. The best conductor of heat from the following options _____?
<p><strong>Mercury</strong> is indeed a liquid metal known for its high thermal conductivity of 8.30 W/(m·K) and its ability to conduct electricity well.</p>
<p>Its unique properties make it useful in various applications, particularly in thermometers, where it accurately reflects temperature changes due to its thermal expansion.</p>
<p>However, due to its toxicity, the use of mercury has been declining in favor of safer alternatives in many devices.</p>
74. Organism that cannot produce its own food known as
<p><strong>Heterotrophs</strong> are organisms that cannot produce their own food and rely on consuming other organisms for energy and nutrients. In contrast, <strong>autotrophs</strong> can produce their own food, typically through photosynthesis or chemosynthesis.</p>
75. Materials which are not attracted by the magnet are known as?
<p>Materials that are not attracted by magnets are referred to as <strong>non-magnetic substances</strong>. Examples include wood, plastic, and most metals except for iron, cobalt, and nickel, which are magnetic.</p>
76. No current passes through the filament of an electric bulb when?
<p><strong>When a bulb is fused</strong>, it means the filament has broken, preventing any current from passing through it.</p>
77. Electricity is produced from Electric cell due to presence of ?
<p>Electricity is produced from an electric cell due to the chemical reactions occurring between the chemicals present in it, which generate electrical energy.</p>
78. If we are able to see clearly through an object and it is allowing light to pass through it, then such kind of objects are known as ________?
<p>Objects that allow light to pass through them without significant scattering, enabling clear visibility, are known as <strong>transparent objects</strong>. Examples include glass, clear plastic, and clean water.</p>
79. Objects that emit or give out light on their own are known as?
<p><strong>Luminous objects</strong> are those that emit or produce light on their own. Examples include the sun, stars, and artificial sources like light bulbs, which generate light independently.</p>
80. If we cannot see anything through an object, then the object is referred as ______?
<p>An object that prevents light from passing through and does not allow visibility through it is called <strong>opaque</strong>. Examples include wood, metals, and thick plastics that block light completely.</p>
81. The metal cap on electric cell indicates _____?
<p>In an electric cell:</p>
<ul>
<li>The <strong>metal cap</strong> represents the <strong>positive terminal</strong>.</li>
<li>The <strong>metal disc</strong> on the bottom serves as the <strong>negative terminal</strong>.</li>
<li>In diagrams, a <strong>longer, thinner line</strong> symbolizes the positive terminal, while a <strong>shorter, thicker line</strong> indicates the negative terminal.</li>
<li>A <strong>line connecting instruments</strong> signifies a wire, and multiple cell symbols together represent a <strong>battery</strong>. This notation is essential for understanding circuit diagrams and electrical schematics.</li>
</ul>
82. The objects through which we cannot see objects clearly are known as?
<p><strong>Translucent objects</strong> permit some light to pass through, but they scatter it, making it difficult to see clearly through them. Examples include frosted glass, wax paper, and certain plastics.</p>
83. The thin wire like object inside the electric bulb which gives light is referred as _____?
<p>The thin, wire-like object inside an electric bulb that emits light when electric current passes through it is known as the <strong>filament</strong>. It is usually made of tungsten, which has a high melting point for durability.</p>
84. Materials which allow current to pass through them are caleed as?
<p>Materials that allow electric current to pass through them are called <strong>conductors</strong>. Examples include metals like copper and aluminum, which are commonly used in electrical wiring.</p>
85. An electric bulb has a filament that is connected to?
<p>The filament of an electric bulb is indeed connected to its <strong>terminals</strong>, supported by thick wires to maintain separation.</p>
<p>When electricity flows through the filament, it heats up due to resistance and produces light, causing the bulb to glow. If the filament breaks, the circuit becomes incomplete, preventing current flow and causing the bulb to go dark. This fundamental principle is essential for understanding how incandescent bulbs function.</p>
86. A rectangular magnet has ___ poles?
<p>A rectangular magnet has <strong>two poles</strong>: a north pole and a south pole. These poles are responsible for the magnet's magnetic field and its ability to attract or repel other magnetic materials.</p>
87. The ______ is captured by the leafs and stored in the plant in the form of food
<p><strong>Solar energy</strong> is captured by the leaves of plants during photosynthesis. This energy is converted into chemical energy, which is stored in the form of food, providing nourishment for the plant.</p>
88. ______ contain acid?
<p><strong>Lemons</strong> contain citric acid, making them acidic. They are known for their sour taste and high vitamin C content. Oranges also contain acid, but lemons are more acidic.</p>
89. Formic acid is found in ______?
<p><strong>Formic acid</strong> is primarily found in the <strong>sting of ants</strong>, which they use as a defense mechanism. It can also be present in some other insects, but it's not found in amla.</p>
90. Magnetite is a ____ magnet?
<p>Magnetite is classified as a <strong>natural magnet</strong> because it occurs naturally in the earth. It possesses inherent magnetic properties, making it one of the strongest naturally occurring magnetic materials.</p>
91. _____ percentage of oceans water is estimated throughout the world?
<p>About <strong>96.5%</strong> of the Earth's total water is estimated to be in the oceans. This vast amount significantly influences global climate, weather patterns, and marine ecosystems across the planet.</p>
92. Collecting rain water and storing it from later use is called as?
<p><strong>Rainwater harvesting</strong> refers to the practice of collecting and storing rainwater for later use. It helps conserve water, reduce runoff, and provides an alternative water source for various needs.</p>
93. Chemical formula for ozone?
<p>Ozone, represented by the chemical formula <strong>O3</strong>, consists of three oxygen atoms. It is a pale blue gas, playing a crucial role in absorbing harmful ultraviolet radiation in the Earth's atmosphere.</p>
94. The major part of air which does not support burning of candle?
<p>The major part of air that does not support burning is <strong>nitrogen</strong>, which makes up about 78% of the Earth's atmosphere and is inert in combustion processes.</p>
95. Carbon monoxide chemical formula?
<p>Carbon monoxide, with the chemical formula <strong>CO</strong>, is a colorless, odorless gas produced from incomplete combustion of carbon-containing fuels. It is toxic and can cause serious health risks.</p>
96. Water vapour gets added to the air by the process of ?
<p>Water vapor is added to the air through <strong>evaporation</strong> from oceans, lakes, and rivers, and <strong>transpiration</strong> from plants. Both processes contribute significantly to the moisture content in the atmosphere.</p>
97. Acidic acid is found in _____?
<p><strong>Acetic acid</strong> is the main component of <strong>vinegar</strong>, contributing to its sour flavor. It is widely used in cooking, food preservation, and as a condiment in various cuisines worldwide.</p>
98. If we look at the mirror we see our own face, this is due to _______?
<p>We see our own face in the mirror due to <strong>reflection</strong>. Light rays bounce off the smooth surface of the mirror, allowing our image to be visible to our eyes.</p>
99. Electricity to the bulb in a torch is provided by the _____ ?
<p>The <strong>electric cell</strong> in a torch supplies electricity to the bulb. It converts stored chemical energy into electrical energy, enabling the bulb to emit light when the circuit is completed.</p>
100. _________ object reflects a beam of light?
<p><strong>Glass</strong> is the object that reflects a beam of light effectively, while wood and paper may scatter light but do not reflect it in a focused manner.</p>
101. An electric bulb glows only when ?
<p>An electric bulb glows only <strong>when an electric current flows through its circuit</strong>. The current heats the filament inside the bulb, causing it to emit light.</p>
102. Objects are materials which does not allow current to pass through them are known as?
<p>Objects that do not allow current to pass through them are known as <strong>insulators</strong>. Common examples include rubber, glass, and plastic, which prevent the flow of electricity.</p>
103. An Example of Insulator is?
<p><strong>Wood</strong> is an example of an insulator, as it does not conduct electricity well.</p>
104. Switch is used for _______ purpose?
<p>A switch is used to control the flow of electricity in a circuit. It allows current to pass, powers electric components, and can also break the circuit when turned off.</p>
105. The magnet attracts magnetic objects due to presence of ______?
<p>Magnets attract magnetic objects due to the presence of <strong>magnetic force</strong>. This force originates from the alignment of magnetic domains within the material, allowing magnets to interact with ferromagnetic substances.</p>
106. The largest gland in the human body is _______
<p>The largest gland in the human body is the<strong> liver</strong>. It performs essential functions such as detoxification, protein synthesis, and production of biochemicals necessary for digestion and metabolism.</p>
107. Amoeba digests its food in the _________
<p>Amoeba digests its food in the <strong>food vacuole</strong>, where enzymes break down the food particles. This process allows the amoeba to absorb nutrients and energy for growth and reproduction.</p>
108. Sometimes the bulb does not glow even though it is connected perfectly, it happens only when the bulb is ______?
<p>A bulb does not glow even when connected perfectly if it is <strong>fused</strong>. A fused bulb means the filament inside is broken, preventing the flow of electricity and light.</p>
109. A bulb is fused only when ?
<p>A bulb is fused when the <strong>filament inside it breaks</strong>, preventing electrical current from flowing. This results in the bulb not lighting up, indicating it needs replacement.</p>