Class 10 Science
Previous Board Examination – Full Solved Answers (Set 3)
All answers are written in simple student exam-writing style, following CBSE board valuation rules.
Section A – MCQs (Answers)
1. Rheostat
2. Less than 7
3. Growth hormone
4. Watt
5. Zinc
Section B – Very Short Answer
6. Define resistance.
Resistance is the property of a conductor by which it opposes the flow of electric current.
7. What is an indicator?
An indicator is a substance that shows whether a solution is acidic or basic by changing colour.
8. Name the part of the brain that controls balance.
Cerebellum
9. Write the chemical formula of plaster of Paris.
CaSO4·½H2O
10. What is pollination?
Pollination is the transfer of pollen grains from the anther to the stigma of a flower.
Section C – Short Answer
11. Define electric power. Write its formula.
Electric power is the rate at which electrical energy is consumed.
Formula: P = VI
12. What is oxidation? Explain with an example.
Oxidation is the process in which a substance gains oxygen or loses hydrogen.
Example: 2Cu + O2 → 2CuO
13. Describe fertilisation in human beings.
Fertilisation is the fusion of male and female gametes.
In humans, the sperm fuses with the ovum in the fallopian tube to form a zygote.
14. Write any three properties of bases.
1. Bases are bitter in taste.
2. They turn red litmus blue.
3. Bases produce OH− ions in water.
15. What is a reflex arc?
A reflex arc is the pathway followed by nerve impulses during a reflex action.
16. Define principal focus of a concave mirror.
The principal focus of a concave mirror is the point on the principal axis where parallel rays of light converge after reflection.
Section D – Long Answer
17. Explain Ohm’s Law.
Ohm’s Law states that at constant temperature, the current flowing through a conductor is directly proportional to the potential difference across it.
V ∝ I or V = IR
18. Describe the properties and uses of ethanol.
Properties:
1. Ethanol is a colourless liquid.
2. It is soluble in water.
3. It is inflammable.
Uses:
1. Used as a fuel.
2. Used in medicines and perfumes.
19. Explain transportation in human beings.
Transportation in humans is carried out by blood.
The heart pumps blood through arteries and veins to supply oxygen and nutrients to all parts of the body.
20. Describe the formation of image by a convex lens.
A convex lens converges light rays.
When the object is placed beyond 2F, the image is formed between F and 2F. It is real, inverted and diminished.
Section E – Case Study Based
21.
a) Calcium carbonate (CaCO3)
b) CaCO3 + 2HCl → CaCl2 + H2O + CO2
c) Avoid using acids on marble surfaces
Shaktimatha CBSE Learning
Class 10 Science – Previous Board Exam Full Answers (Set 3)
⬅️ Back to Class 10 Science Library
🔬 Class 10 Science – Previous Board Question Papers & Full Answers
This complete library is designed for Class 10 CBSE students to practise previous board exam papers and learn how to write perfect answers in Physics, Chemistry, and Biology.
📝 Previous Board Question Papers
- Question Paper – Set 1
- Question Paper – Set 2
- Question Paper – Set 3
- Question Paper – Set 4
- Question Paper – Set 5
✍️ Full Answers (Student Writing Style)
- Full Answers – Set 1
- Full Answers – Set 2
- Full Answers – Set 3
- Full Answers – Set 4
- Full Answers – Set 5
📚 Additional Board Sets (Practice)
- Additional Question Paper – Set 1A
- Additional Full Answers – Set 1A
- Additional Question Paper – Set 2A
- Additional Full Answers – Set 2A
- Additional Question Paper – Set 3A
- Additional Full Answers – Set 3A
✔ First attempt the question paper on your own
✔ Then compare with full answers
✔ Observe diagrams, keywords, and steps
✔ Practise again to improve speed and accuracy
Prepared with dedication by Shaktimatha Learning ✨
Clear concepts • Exam confidence • Board success
.png)
No comments:
Post a Comment