Bihar Board Class 10 · Science · Matric exam 2027
Bihar Board Class 10 Science Question Paper 2026
The board’s 2026 question paper, set E — all 107 questions as printed; 77 objective answers from the board’s own key; full model answers for 3 written questions, how the answer begins for 27 more. Each question names its chapter, where that chapter’s most-asked questions are.
Full marks 80 · Time 2 h 45 min
Section A · Objective questions (77)
An ore of mercury is
- (A) Bauxite
- (B) Haematite
- (C) Magnetite
- (D) Cinnabar ✓
Answer (the board’s key): (D)
Which of the following is the least reactive metal ?
- (A) Mg
- (B) Fe ✓
- (C) Zn
- (D) Al
Answer (the board’s key): (B)
Which of the following is a hydrocarbon ?
- (A) H2O
- (B) C4H10 ✓
- (C) CO2
- (D) HNO3
Answer (the board’s key): (B)
- OH is the functional group of
- (A) Ketone
- (B) Alcohol ✓
- (C) Aldehyde
- (D) None of these
Answer (the board’s key): (B)
How many covalent bonds are there in methane ?
- (A) 2
- (B) 4 ✓
- (C) 6
- (D) 8
Answer (the board’s key): (B)
The shape of C60 Fullerene is similar to which of the following ?
- (A) Pear
- (B) Damru
- (C) Football ✓
- (D) None of these
Answer (the board’s key): (C)
Carbon belongs to which group of the periodic table ?
- (A) 3
- (B) 13
- (C) 6
- (D) 14 ✓
Answer (the board’s key): (D)
How many periods are there in the periodic table ?
- (A) 5
- (B) 6
- (C) 7 ✓
- (D) 8
Answer (the board’s key): (C)
Which gas is responsible for global warming ?
- (A) O_2
- (B) NH_3
- (C) N_2
- (D) CO_2 ✓
Answer (the board’s key): (D)
The main component of domestic gas ( LPG ) is
- (A) Methane
- (B) Butane ✓
- (C) Ethane
- (D) Propane
Answer (the board’s key): (B)
An example of fossil fuel is
- (A) Petroleum products
- (B) Coal
- (C) Both (A) and (B) ✓
- (D) None of these
Answer (the board’s key): (C)
The reaction in which heat is evolved along with the formation of products is called
- (A) exothermic ✓
- (B) endothermic
- (C) photosynthesis
- (D) oxidation
Answer (the board’s key): (A)
The reaction 2Cu + O_2 -> 2CuO is which type of chemical reaction ?
- (A) Oxidation ✓
- (B) Reduction
- (C) Displacement
- (D) Neutralization
Answer (the board’s key): (A)
Which of the following is an oxidant ?
- (A) H_2
- (B) CO
- (C) O_3 ✓
- (D) H_2S
Answer (the board’s key): (C)
In electrolysis, electrons are liberated at
- (A) anode ✓
- (B) cathode
- (C) both (A) and (B)
- (D) none of these
Answer (the board’s key): (A)
Which of the following metals can displace zinc from zinc sulphate solution ?
- (A) Sn
- (B) Fe
- (C) Mg ✓
- (D) Cu
Answer (the board’s key): (C)
Under whose leadership was the 'Chipko Movement' started ?
- (A) Amrita Devi Bishnoi
- (B) Sunderlal Bahuguna
- (C) Chandi Prasad Bhatt
- (D) Both (B) and (C) ✓
Answer (the board’s key): (D)
Which of the following is the main source of energy on earth ?
- (A) Coal
- (B) Water
- (C) Air
- (D) Sunlight ✓
Answer (the board’s key): (D)
Katta is the water storage system of which state ?
- (A) Kerala
- (B) Karnataka ✓
- (C) Tamil Nadu
- (D) Bihar
Answer (the board’s key): (B)
Which is used in solar cells ?
- (A) Uranium
- (B) Plutonium
- (C) Silicon ✓
- (D) None of these
Answer (the board’s key): (C)
Amoeba takes in its food by
- (A) teeth
- (B) food vacuole
- (C) pseudopodia ✓
- (D) the nucleus
Answer (the board’s key): (C)
The angle of incidence equals the angle of reflection according to
- (A) Newton's law
- (B) Snell's law
- (C) Law of reflection ✓
- (D) Fermat's principle
Answer (the board’s key): (C)
The image formed by a plane mirror is
- (A) Real
- (B) Virtual ✓
- (C) Both (A) and (B)
- (D) None of these
Answer (the board’s key): (B)
Which of the following is made in a pin hole camera ?
- (A) Shadow
- (B) Image ✓
- (C) Hologram
- (D) None of these
Answer (the board’s key): (B)
If the angle of incidence is 45°, then the angle between the reflected ray and the normal will be
- (A) less than 45°
- (B) 45° ✓
- (C) more than 45°
- (D) none of these
Answer (the board’s key): (B)
Which of the following is a relatively denser medium for light ?
- (A) Water
- (B) Air
- (C) Kerosene ✓
- (D) None of these
Answer (the board’s key): (C)
The magnification of the image of the moon by a convex mirror will be
- (A) 1
- (B) -1
- (C) negligible ✓
- (D) None of these
Answer (the board’s key): (C)
The speed of light is maximum in
- (A) air
- (B) glass
- (C) vacuum ✓
- (D) none of these
Answer (the board’s key): (C)
In an optical fibre, the light undergoes
- (A) total internal reflection ✓
- (B) reflection
- (C) dispersion of colours
- (D) none of these
Answer (the board’s key): (A)
An example of geotropism is
- (A) growth of stem
- (B) growth of root
- (C) growth of fruit
- (D) both (A) and (B) ✓
Answer (the board’s key): (D)
In which of the following does binary fission occur?
- (A) Amoeba
- (B) Paramoecium
- (C) Euglena
- (D) All of these ✓
Answer (the board’s key): (D)
Which of the following is a sexually transmitted disease?
- (A) AIDS
- (B) Gonorrhoea
- (C) Typhoid
- (D) Both (A) and (B) ✓
Answer (the board’s key): (D)
The seed develops from
- (A) Ovule ✓
- (B) Anther
- (C) Ovary
- (D) Stamen
Answer (the board’s key): (A)
The number of autosomes in humans is
- (A) 22 pairs ✓
- (B) 23 pairs
- (C) 11 pairs
- (D) 24 pairs
Answer (the board’s key): (A)
Which of the following is a non-biodegradable substance?
- (A) DDT ✓
- (B) Paper
- (C) Sewage
- (D) None of these
Answer (the board’s key): (A)
Tiger is a consumer of
- (A) First trophic level
- (B) Second trophic level
- (C) Third trophic level ✓
- (D) None of these
Answer (the board’s key): (C)
Which of the following is a decomposer?
- (A) Algae
- (B) Round worm
- (C) Bacteria ✓
- (D) Amarbel
Answer (the board’s key): (C)
In which part of the alimentary canal is the digestion process completed?
- (A) In the stomach
- (B) In the colon
- (C) In the oesophagus
- (D) In the small intestine ✓
Answer (the board’s key): (D)
An example of saprophyte is
- (A) Amoeba
- (B) Amarbel
- (C) Hibiscus
- (D) Mushroom ✓
Answer (the board’s key): (D)
Bile juice is secreted from
- (A) Pancreas
- (B) Stomach
- (C) Liver ✓
- (D) Salivary gland
Answer (the board’s key): (C)
The main respiratory organ of fish is
- (A) Lungs
- (B) Trachea
- (C) Nose
- (D) Gills ✓
Answer (the board’s key): (D)
What is called cellular fuel?
- (A) Fat
- (B) Protein
- (C) Glucose ✓
- (D) None of these
Answer (the board’s key): (C)
Fermentation process is found in
- (A) Amoeba
- (B) Yeast ✓
- (C) Hydra
- (D) None of these
Answer (the board’s key): (B)
What is blood?
- (A) Connective tissue ✓
- (B) Epithelium
- (C) Fat
- (D) None of these
Answer (the board’s key): (A)
The human heart is a part of which system?
- (A) Digestion
- (B) Respiration
- (C) Excretion
- (D) Transportation ✓
Answer (the board’s key): (D)
Which of the following combinations increases the value of resistance?
- (A) Series ✓
- (B) Parallel
- (C) Both (A) and (B)
- (D) None of these
Answer (the board’s key): (A)
The charge carriers in metal are
- (A) Electrons ✓
- (B) Protons
- (C) Neutrons
- (D) None of these
Answer (the board’s key): (A)
What kind of conductor is pure water ?
- (A) Conductor
- (B) Bad conductor ✓
- (C) Super conductor
- (D) None of these
Answer (the board’s key): (B)
Which of the following is the best conductor ?
- (A) Aluminium
- (B) Copper
- (C) Silver ✓
- (D) None of these
Answer (the board’s key): (C)
Who discovered the magnetic effect of electric current ?
- (A) Oersted ✓
- (B) Ampere
- (C) Bohr
- (D) Faraday
Answer (the board’s key): (A)
What does the middle finger of Fleming's left hand rule indicate ?
- (A) Direction of electric force applied on the conductor
- (B) Direction of electric current in the conductor ✓
- (C) Direction of the magnetic field
- (D) None of these
Answer (the board’s key): (B)
The frequency of alternating current supplied to houses in India is
- (A) 50 Hz ✓
- (B) 60 Hz
- (C) 70 Hz
- (D) None of these
Answer (the board’s key): (A)
The melting point of a fuse should be
- (A) low ✓
- (B) high
- (C) very high
- (D) none of these
Answer (the board’s key): (A)
Which of the following is water-conducting tissue in plants ?
- (A) Xylem ✓
- (B) Phloem
- (C) Sieve tube
- (D) Root hair
Answer (the board’s key): (A)
The main function of kidney is
- (A) reproduction
- (B) digestion
- (C) formation of ATP
- (D) excretion ✓
Answer (the board’s key): (D)
Plant wastes are stored in the
- (A) bark
- (B) cellular vacuoles
- (C) leaves
- (D) all of these ✓
Answer (the board’s key): (D)
The excretory substances of plants are
- (A) glue
- (B) tanin
- (C) resin
- (D) all of these ✓
Answer (the board’s key): (D)
Which of the following is formed by the breakdown of amino acid ?
- (A) CO
- (B) CO2
- (C) NH3 ✓
- (D) SO2
Answer (the board’s key): (C)
Which of the following diseases is caused by the deficiency of insulin ?
- (A) Goitre
- (B) Cretinism
- (C) Dwarfism
- (D) Diabetes ✓
Answer (the board’s key): (D)
Which of the following is an example of reflex action ?
- (A) Sneezing
- (B) Mouth watering after seeing sweets
- (C) Blinking of eyes
- (D) All of these ✓
Answer (the board’s key): (D)
What is estrogen ?
- (A) Male hormone
- (B) Female hormone ✓
- (C) Digestive juice
- (D) None of these
Answer (the board’s key): (B)
Chemical formula of marble is
- (A) MgCO3
- (B) CaO
- (C) CaCO3 ✓
- (D) CuSO4
Answer (the board’s key): (C)
Which of the following is a strong acid ?
- (A) H2SO4
- (B) HCl
- (C) HNO3
- (D) All of these ✓
Answer (the board’s key): (D)
A solution turns blue litmus paper, red. Its pH will be probably
- (A) 5 ✓
- (B) 7
- (C) 8
- (D) 11
Answer (the board’s key): (A)
Which of the following is slaked lime ?
- (A) CaO
- (B) Ca(OH)2 ✓
- (C) CaCO3
- (D) Ca
Answer (the board’s key): (B)
Which of the following is a natural source of oxalic acid ?
- (A) Orange
- (B) Tomato ✓
- (C) Vinegar
- (D) Tamarind
Answer (the board’s key): (B)
Which of the following is a non-metal ?
- (A) Fe
- (B) C ✓
- (C) Al
- (D) Au
Answer (the board’s key): (B)
How many electrons are there in the outer orbit of helium atom ?
- (A) 1
- (B) 2 ✓
- (C) 3
- (D) None of these
Answer (the board’s key): (B)
An alloy of lead and tin is
- (A) Solder ✓
- (B) Steel
- (C) Bronze
- (D) None of these
Answer (the board’s key): (A)
Which of the following lenses is called a converging lens ?
- (A) Concave lens
- (B) Convex lens ✓
- (C) Both (A) and (B)
- (D) Bifocal
Answer (the board’s key): (B)
The SI unit of power of the lens is
- (A) cm^-1
- (B) cm
- (C) m^-1 ✓
- (D) m
Answer (the board’s key): (C)
The distance between the eye lens and the retina is approximately
- (A) 25 cm
- (B) 1 cm
- (C) 2.5 cm ✓
- (D) 5 cm
Answer (the board’s key): (C)
Which type of lens is found in the human eye ?
- (A) Convex ✓
- (B) Concave
- (C) Cylindrical
- (D) Bifocal
Answer (the board’s key): (A)
Which of the following lenses is used to correct near sightedness ?
- (A) Concave lens ✓
- (B) Convex lens
- (C) Planoconvex lens
- (D) None of these
Answer (the board’s key): (A)
Which colour of light is scattered least in the atmosphere ?
- (A) Red ✓
- (B) Blue
- (C) Yellow
- (D) Green
Answer (the board’s key): (A)
Which colour deviates minimum in a glass prism ?
- (A) Red ✓
- (B) Yellow
- (C) Blue
- (D) Violet
Answer (the board’s key): (A)
Which instrument does not have positive (+) and negative (-) signs ?
- (A) Voltmeter
- (B) An electric cell
- (C) Ammeter
- (D) Solenoid ✓
Answer (the board’s key): (D)
Section B · Written questions (30)
Why is a concave lens called a diverging lens ?
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Model answer · diverging action, concave lens
- 1.A concave lens spreads out the light rays coming parallel to its principal axis after refraction. Several rays of light parallel to the principal axis fall on a concave lens, and these rays, after refraction from the lens, appear to diverge from a point on the principal axis.1 mark
- 2.Due to this property of diverging the light rays, a concave lens is called a diverging lens.1 mark
- Mention that parallel rays falling on the concave lens, after refraction, appear to diverge from a point on the principal axis.
- End by clearly stating that this diverging property is why the concave lens is called a diverging lens.
Marks split from a structure derived from past papers (checked twice); not Bihar Board’s official scheme
Write down Snell's law.
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Model answer · Snell's law of refraction
- 1.The ratio of sine of angle of incidence to the sine of angle of refraction is a constant, for the light of a given colour and for the given pair of media. This law is also known as Snell's law of refraction.1 mark
- 2.This constant value is called the refractive index of the second medium with respect to the first. If i is the angle of incidence and r is the angle of refraction, then sin i / sin r = μ.1 mark
- Write the exact phrase 'sine of angle of incidence to the sine of angle of refraction is a constant'.
- State clearly that this constant is called the refractive index.
- Write the relation sin i / sin r = μ using the letters i, r, and μ.
Marks split from a structure derived from past papers (checked twice); not Bihar Board’s official scheme
Why is the railway signal light always red in colour ?
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Model answer · scattering of light, red signal
- 1.Red colour has a wavelength that is longer among the colours of light, as the red light has a wavelength about 1.8 times greater than blue light.1 mark
- 2.The red colour is least scattered by fog or smoke because fine particles are more effective in scattering light of shorter wavelengths than light of longer wavelengths. Therefore, the red signal light can be seen in the same colour at a distance, which is why railway signal lights are red in colour.1 mark
- Write the word 'wavelength' and mention that red has a longer wavelength than other colours.
- Write the word 'scattered' or 'scattering' and state that red is least scattered by fog or smoke.
- Connect the fact to visibility at a distance, as the signal must be clearly seen.
Marks split from a structure derived from past papers (checked twice); not Bihar Board’s official scheme
Define the strength of electric current.
How the model answer begins
1. The intensity of electric current is defined as the amount of charge flowing through a cross-section of a conductor per unit time. If a net charge Q flows across any cross-section of a conductor in time t, then this…
The full answer from Medha Ma’am →What is resistance ? Write its SI unit.
How the model answer begins
1. Resistance is the property of a conductor to resist the flow of charges through it.
The full answer from Medha Ma’am →Write Fleming's right hand rule.
How the model answer begins
1. Fleming's right-hand rule states that we should stretch the thumb, forefinger and middle finger of right hand so that they are perpendicular to each other.
The full answer from Medha Ma’am →What is geothermal energy ?
How the model answer begins
1. The heat energy generated from the hot rocks or magma located deep inside the earth is called geothermal energy. Due to geological changes, molten rocks formed in the deeper hot regions of earth's crust are pushed…
The full answer from Medha Ma’am →What are the functions of producers in the ecosystem ?
How the model answer begins
1. Producers synthesize food by converting solar energy into chemical energy. All green plants and certain blue-green algae which can produce food by photosynthesis are called the producers, and they capture the energy…
The full answer from Medha Ma’am →Describe the electric motor along with its principle.
How the model answer begins
1. An electric motor works on the principle of the magnetic effect of electric current. A current-carrying conductor when placed in a magnetic field experiences a force, and if the direction of the field and that of the…
The full answer from Medha Ma’am →What steps have been taken to limit ozone depletion ?
How the model answer begins
1. In 1987, the United Nations Environment Programme (UNEP) succeeded in forging an agreement to freeze CFC production at 1986 levels. This agreement, known as the Montreal Protocol, was adopted to prevent the depletion of…
The full answer from Medha Ma’am →What is a balanced chemical equation ? Give an example.
How the model answer begins
1. A balanced chemical equation is a chemical equation in which the number of atoms of each element in the reactants and products is equal.
The full answer from Medha Ma’am →What do you understand by electrolysis ?
How the model answer begins
1. Electrolysis is a process in which chemical decomposition occurs when an electric current is passed through an aqueous solution or molten state of an electrolyte. For example, when electricity is passed through an…
The full answer from Medha Ma’am →What is a base ? What is the difference between a base and an alkali ?
How the model answer begins
1. Bases are substances that are bitter in taste and turn red litmus paper blue.
The full answer from Medha Ma’am →What are called minerals ?
How the model answer begins
1. The elements or compounds, which occur naturally in the earth's crust, are known as minerals.
The full answer from Medha Ma’am →What is called ductility ?
How the model answer begins
1. The ability of metals to be drawn into thin wires is called ductility. This property of metals by which they can be drawn into thin wires is one of the important physical properties of metals.
The full answer from Medha Ma’am →What is isomerism ? Give one example.
How the model answer begins
1. Compounds having the same molecular formula but different structures are called isomers and this phenomenon is known as isomerism.
The full answer from Medha Ma’am →What is the modern periodic law ?
How the model answer begins
1. According to the Modern Periodic Law, the properties of elements are a periodic function of their atomic number. This means that when elements are arranged in order of increasing atomic number, elements with similar…
The full answer from Medha Ma’am →What is water harvesting ?
How the model answer begins
1. Water harvesting is the process of collecting rainwater and conserving it for future use.
The full answer from Medha Ma’am →What is pH ? State the importance of pH in daily life.
How the model answer begins
1. pH is a scale used to measure the hydrogen ion concentration in a solution. On the pH scale we can measure pH generally from 0 (very acidic) to 14 (very alkaline). Higher the hydronium ion concentration, lower is the pH…
The full answer from Medha Ma’am →What is 'Chipko movement' ? Explain it.
How the model answer begins
1. The Chipko movement, also called Chipko Andolan or 'Hug the Trees Movement', was a non-violent movement started by local people as a grassroot level effort to end the alienation of people from their forests and to save…
The full answer from Medha Ma’am →What is the role of digestive juice in the stomach ?
How the model answer begins
1. Gastric glands present in the wall of the stomach release gastric juice which contains hydrochloric acid, a protein digesting enzyme called pepsin, and mucus.
The full answer from Medha Ma’am →What is fermentation ? Write its equation.
How the model answer begins
1. Fermentation is the process in which the pyruvate formed from the breakdown of glucose is converted into ethanol and carbon dioxide by yeast. Since this process takes place in the absence of air (oxygen), it is called…
The full answer from Medha Ma’am →How are water and mineral salts transported in plants ?
How the model answer begins
1. In plants, the transport of water and mineral salts occurs through xylem tissue. Vessels and tracheids of the roots, stems and leaves are interconnected to form a continuous system of water-conducting channels reaching…
The full answer from Medha Ma’am →Define excretion. What is an excretory substance ?
How the model answer begins
1. Excretion is the biological process involved in the removal of harmful metabolic wastes, that is, nitrogenous materials generated due to metabolic activities, from the body of organisms.
The full answer from Medha Ma’am →What is the difference between reflex action and reflex arc ?
How the model answer begins
1. Reflex action is an involuntary and rapid response that occurs suddenly in response to a stimulus, such as pulling our hand back from a flame.
The full answer from Medha Ma’am →What is the difference between self-pollination and cross-pollination ?
How the model answer begins
1. Self-pollination is the transfer of pollen grains from the anther to the stigma of the same flower or another flower of the same plant.
The full answer from Medha Ma’am →Define genotype and phenotype.
How the model answer begins
1. Genotype represents the genetic constitution or the combination of genes of an organism. It is the set of genes that an organism inherits from its parents and decides the traits that may be expressed. Thus, the genotype…
The full answer from Medha Ma’am →What do you understand by homologous organs ? Give examples.
How the model answer begins
1. Organs which have the same basic structure and origin but perform different functions are called homologous organs. Such a homologous characteristic helps to identify an evolutionary relationship between apparently…
The full answer from Medha Ma’am →What is nutrition ? Describe the different modes of nutrition found in living organisms.
How the model answer begins
1. Nutrition is the process by which organisms take in food and utilize it for obtaining energy and body growth. Food is the source of energy and of the materials the body needs to grow, develop and synthesise protein.…
The full answer from Medha Ma’am →What are the advantages of sexual reproduction over asexual reproduction ?
How the model answer begins
1. The main advantage of sexual reproduction is that it produces much more variation. In sexual reproduction, DNA from two different individuals, a male and a female, is combined. Each offspring therefore gets a new…
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