MCQS (class10 science) 50's important MCQ for board exam

 Class 10 Science MCQs are designed according to the NCERT syllabus and are an excellent way for students to test their understanding in preparation for board exams. These questions cover all the key topics in Physics, Chemistry, Biology, and Environmental Science. Practicing these MCQs helps improve knowledge, problem-solving skills, and time management, making students more confident and better prepared for their exams.

1. What is the SI unit of force?
a) Pascal
b) Joule
c) Newton
d) Watt

2. Which of the following is a non-renewable resource?
a) Coal
b) Solar energy
c) Biomass
d) Wind energy

3. What is the primary function of the human digestive system?
a) To regulate temperature
b) To circulate blood
c) To break down food and absorb nutrients
d) To provide oxygen to the body

4. Which part of the plant is responsible for photosynthesis?
a) Roots
b) Leaves
c) Stem
d) Flowers

5. What is the atomic number of an element?
a) The number of neutrons in the nucleus of an atom
b) The total number of protons and neutrons in an atom
c) The number of protons in the nucleus of an atom
d) The number of electrons in an atom

6. What is the purpose of a fuse in an electrical circuit?

a) To store energy
b) To regulate voltage
c) To increase the current flow
d) To protect the circuit from excessive current

7. Which part of the brain controls balance and coordination?
a) Medulla oblongata
b) Thalamus
c) Cerebellum
d) Cerebrum

8.  Which of the following is a characteristic of asexual reproduction?
a) Requires sexual organs
b) Involves two parents
c) Occurs only in plants
d) Offspring are genetically identical to the parent

9.  Which gas is responsible for the greenhouse effect?
a) Carbon dioxide
b) Oxygen
c) Hydrogen
d) Nitrogen

10.  What is the pH value of pure water?
a) 7
b) 5
c) 9
d) 11

11.  What type of lens is used to correct short-sightedness?
a) Cylindrical lens
b) Concave lens
c) Convex lens
d) Bifocal lens

12. What is the function of hemoglobin in the blood?
a) Fighting infections
b) Clotting blood
c) Transporting oxygen
d) Breaking down glucose

13. What is the primary purpose of vaccines?

a) Heal wounds
b) Provide nutrition
c) Prevent infections
d) Relieve pain

14. Which vitamin is known as ascorbic acid?

a) Vitamin C
b) Vitamin D
c) Vitamin A
d) Vitamin B

15. Which of the following is a chemical reaction?

a) Melting ice
b) Boiling water
c) Dissolving sugar in water
d) Burning of wood

16. Which type of reaction is represented by A + B → AB?

a) Double displacement
b) Displacement
c) Combination
d) Decomposition

17. Which of the following salts is formed when hydrochloric acid reacts with sodium hydroxide?

a) Sodium sulfate
b) Sodium chloride
c) Sodium carbonate
d) Sodium nitrate

18.  Which gas is evolved when an acid reacts with a metal?

a) Carbon dioxide
b) Oxygen
c) Nitrogen
d) Hydrogen

19.  What is formed when iron reacts with moist air?

a) Rust
b) Aluminum oxide
c) Copper
d) Zinc

20.  Which metal is commonly used in electrical wiring?

a) Zinc
b) Copper
c) Lead
d) Iron

21. Which of the following is an alcohol?

a) Propane
b) Butane
c) Methane
d) Ethanol

22. Which organ in humans is responsible for the filtration of blood?

a) Heart
b) Kidney
c) Lungs
d) Liver

23.  Which of the following is responsible for the transportation of water in plants?

a) Xylem
b) Phloem
c) Root hairs
d) Leaves

24. What is the process of fusion of male and female gametes called?

a) Regeneration
b) Fertilization
c) Pollination
d) Fragmentation

25. Which of the following is used in the production of fertilizers?

a) Sulphur
b) Phosphorus
c) Nitrogen
d) All of the mentioned

26. What is the main purpose of meiosis in reproduction?

a) To produce genetically identical cells
b) To reduce chromosome number by half
c) To form new offspring
d) To produce energy

28.  What determines the sex of a human baby?

a) Father’s chromosomes
b) Environmental factors
c) Mother’s chromosomes
d) Number of genes

29.  What is the law of reflection?

a) Angle of incidence equals the angle of refraction
b) Angle of incidence equals the angle of reflection
c) Angle of incidence is greater than the angle of reflection
d) None of the mentioned

30.  What happens when light passes from air to water?

a) It bends towards the normal
b) It remains straight
c) It bends away from the normal
d) It reflects back

31.  What is the focal length of a lens?

a) The distance between the object and the lens
b) The distance between the lens and its focus
c) The distance between the image and the lens
d) The distance between the lens and the retina

32. What is the cause of dispersion of light through a prism?

a) Refraction
b) Reflection
c) Interference
d) Scattering

33. What is the SI unit of electric current?

a) Volt
b) Ohm
c) Ampere
d) Coulomb

34.  What is the device used to measure current in a circuit?

a) Voltmeter
b) Ohmmeter
c) Galvanometer
d) Ammeter

35.  A solenoid is a coil of wire. When a current flows through the solenoid, what does it produce?

a) Gravitational force
b) Magnetic field
c) Electric field
d) Sound waves

36.  What is the main component of smog?

a) Carbon monoxide
b) Sulfur dioxide
c) Nitrogen dioxide
d) Water vapor

37. What is the primary cause of acid rain?

a) Carbon dioxide
b) Ozone depletion
c) Nitrogen oxides and sulfur dioxide
d) Overuse of pesticides

38. . What are decomposers in an ecosystem?

a) Plants
b) Animals
c) Herbivores
d) Microorganisms

39.  What is the color change when litmus paper is dipped in acid?

a) Blue to red
b) Red to blue
c) No change
d) Red to yellow

40. What is the primary function of the stomata in plants?

a) To absorb water
b) To release oxygen
c) To take in carbon dioxide
d) To produce food

41.  Which of these is not a part of the circulatory system in humans?

a) Kidneys
b) Heart
c) Blood
d) Lungs

42. What is the process by which plants prepare their food?
a) Respiration
b) Photosynthesis
c) Digestion
d) Transpiration

43. What is the main ore of aluminum?
a) Bauxite
b) Hematite
c) Galena
d) Magnetite

44. Which is the longest cell in the human body?

a) Nerve cell
b) Red blood cell
c) White blood cell
d) Muscle cell

45. Which gland is known as the “master gland”?
a) Thyroid
b) Pituitary
c) Pancreas
d) Adrenal

47. Which part of the eye controls the amount of light entering it?
a) Retina
b) Cornea
c) Iris
d) Optic nerve