Hello students! If you are preparing for the UP Board Class 10th Board Exam 2026, then today's post is highly important for you. In this article, we have completely solved the Science Paper Set 824 (IO) with detailed explanations.
Doston, agar aap UP Board Exam 2026 ki taiyari kar rahe hain aur vigyan (Science) mein achhe marks lana chahte hain, toh aaj ki ye post aapke liye game-changer saabit hone wali hai. Aksar students internet par Class 10 Science Important Questions 2026 UP Board dhoondhte hain, lekin unhe specific paper ka hal nahi mil pata.
Isiliye, aaj main aapke liye lekar aaya hoon poora UP Board Class 10 Science Solved Paper 2026 Set 824 IO. Chahe aap Hindi medium ke student hon ya English medium ke (aap humari website ka Translate button use kar sakte hain), ye post dono ke liye behad zaroori hai. Is post mein humne Science paper set 824 (IO) solution ko detail mein cover kiya hai, jisme Physics ke ray diagrams se lekar Chemistry aur Biology ke sabhi mahatvapurn Multiple Choice Questions (MCQs) shamil hain.
Previous year papers aur latest model paper ke pattern par aadharit ye UP Board 10th Science Paper Set 824 (IO) Solved aapki aakhiri samay ki revision (last-minute preparation) ko bahut majboot bana dega. Toh chaliye, bina waqt barbad kiye in prashno ko hal karte hain!
Part A: Multiple Choice Questions (MCQs)
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Ans: (A) Convex lens of 10 cm focal length.Explanation: To read small letters, we need a lens that forms a magnified and clear image of the object. A convex lens is used as a magnifying glass. When an object is placed within the focus of a convex lens, it forms a virtual, erect, and magnified image. A convex lens of shorter focal length (10 cm) provides greater magnification, making it the most suitable choice.
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Ans: (C) Atmospheric refraction.Explanation: The twinkling of stars is caused by atmospheric refraction. The Earth's atmosphere consists of layers with varying optical densities. When starlight passes through these layers, it undergoes continuous refraction. Because of this, the amount of starlight reaching our eyes fluctuates, causing the star to appear to twinkle.
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Ans: (B) Virtual and diminished.Explanation: A convex mirror always forms a virtual, erect, and diminished image regardless of the object's position. When an object is at infinity, its image is formed at the principal focus behind the mirror. This image is highly diminished (point-sized) and virtual.
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Ans: (D) Violet.Explanation: When white light passes through a glass prism, it splits into its constituent seven colors (dispersion). Each color has a different refractive index. Violet light has the shortest wavelength and the highest refractive index, so it bends the most, resulting in the largest angle of deviation.
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Ans: (C) Charge.Explanation: The SI unit of electric charge is the Coulomb. One Coulomb is defined as the amount of charge transferred when a current of one Ampere flows for one second. Therefore, Charge (Q) = Current (I) × Time (t) = Ampere × Second. Hence, Ampere-second is the unit of electric charge.
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Ans: (C) 9/2.Explanation:
In series, equivalent resistance $R_1 = R + 2R = 3R$.
In parallel, equivalent resistance $1/R_2 = 1/R + 1/2R = 3/2R$, which means $R_2 = 2R/3$.
Therefore, the ratio $\frac{R_1}{R_2} = \frac{3R}{2R/3} = \frac{9}{2}$.
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Ans: (A) -CHO.Explanation: Propanal belongs to the aldehyde group, indicated by the suffix '-al'. The functional group for aldehydes is the -CHO group.
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Ans: (A) 7.Explanation: A perfectly neutral solution, such as pure distilled water at room temperature, has a pH value of exactly 7.
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Ans: (C) K (Potassium).Explanation: Potassium (K) is a highly reactive alkali metal that sits at the top of the reactivity series. It reacts violently with cold water to form potassium hydroxide and hydrogen gas.
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Ans: (B) ATP.Explanation: ATP (Adenosine Triphosphate) is known as the energy currency of the cell. It stores and provides the energy required for almost all cellular processes.
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Ans: (B) Liver.Explanation: Bile juice is produced and secreted by the liver. It is then stored and concentrated in the gall bladder until it is needed for digestion.
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Ans: (C) Green plants.Explanation: Green plants are autotrophs. They synthesize their own food using sunlight, carbon dioxide, and water through the process of photosynthesis, making them the primary producers in an ecosystem.
Part B – Descriptive Questions (Solved)
Scattering of light causes many beautiful phenomena in nature. Two examples are:
1. The blue color of the clear sky: When sunlight enters the Earth's atmosphere, fine particles and gas molecules scatter the shorter-wavelength blue light much more efficiently than other colors, making the sky appear blue.
2. The reddish appearance of the Sun at sunrise and sunset: During these times, light has to travel through a thicker layer of the atmosphere. Most of the shorter wavelengths (like blue) are scattered away, allowing predominantly the longer-wavelength red light to reach our eyes.
Fleming’s Left-Hand Rule determines the direction of the force acting on a current-carrying conductor placed in a magnetic field.
According to this rule: If we stretch the thumb, forefinger, and middle finger of our left hand mutually perpendicular to each other, such that:
• The forefinger points in the direction of the magnetic field.
• The middle finger points in the direction of the electric current.
• Then, the thumb will point in the direction of the force acting on the conductor (or the direction of motion).
This principle is widely used in the working of electric motors.
[Image of concave lens ray diagram]
[Image of magnetic field lines around a bar magnet]
The IUPAC nomenclature system provides standard scientific names for organic compounds.
(i) Acetylene: Its IUPAC name is Ethyne. It is an unsaturated hydrocarbon containing a triple bond between two carbon atoms (Formula: C2H2).
(ii) Acetic acid: Its IUPAC name is Ethanoic Acid. It is a carboxylic acid containing the functional group -COOH (Formula: CH3COOH).
Ethanol (C2H5OH) is an important organic compound. Two major chemical reactions of ethanol are:
1. Combustion Reaction: Ethanol burns readily in the air (oxygen) to produce carbon dioxide, water, and heat/light energy.
C2H5OH + 3O2 → 2CO2 + 3H2O + Heat
2. Esterification Reaction: Ethanol reacts with ethanoic acid in the presence of concentrated sulfuric acid (as a catalyst) to form a sweet-smelling substance called an ester (ethyl ethanoate).
CH3COOH + C2H5OH → CH3COOC2H5 + H2O
A synapse is the microscopic gap or junction between the nerve ending (axon terminal) of one neuron and the dendrite of the adjacent neuron.
When an electrical nerve impulse reaches the end of the axon, it stimulates the release of chemical messengers known as neurotransmitters. These chemicals diffuse across the synapse and bind to receptors on the next neuron, triggering a new electrical impulse. This mechanism ensures that nerve signals travel in one direction throughout the nervous system, facilitating coordination and response. [Image of structure of synapse]
Conclusion
Students, we hope you found this post on the UP Board Class 10 Science Solved Paper 2026 useful. Make sure to note down all these questions and practice the diagrams, as they are highly important for your upcoming Board Exams.
Frequently Asked Questions (FAQs)
Q1. Are these exact questions expected in the 2026 Board Exams?
Ans: These questions are based on the latest UP Board syllabus and past year papers, making them highly probable and excellent for practice.
Q2. How can I score better marks in the Science exam?
Ans: To score well, practice MCQs daily, understand the concepts instead of memorizing, and practice drawing neat and labeled diagrams (like ray diagrams and magnetic fields) yourself.
