Overview

Previous Year UPSC-CSE Questions By the end you will be able to draft model answers for the following UPSC questions. Each question carries a collapsible framework showing how to approach it in the exam.

  1. UPSC Prelims 2006 GS-IMatch the finding, invention or calculation in List-I with the ancient Indian scholar in List-II, where List-II is 1. Aryabhatta, 2. Bhaskaracharya, 3. Budhayana, 4. Gyandev. List-I is:
    1. A. Time taken by the Earth to orbit the Sun
    2. B. Calculation of the value of 'pi'
    3. C. Invention of the digit zero
    4. D. The game of snakes and ladders

    Select the correct code:

    1. a A 2 B 4 C 1 D 3
    2. b A 2 B 3 C 1 D 4
    3. c A 1 B 3 C 2 D 4
    4. d A 1 B 4 C 2 D 3
    How to approach this Prelims question

    Question type: Match-the-list question pairing four findings with four Indian scholars.

    Approach: Anchor the one sure Gupta-age pairing first: the digit zero goes with Aryabhata (option C with 1); that alone fixes the answer as the option reading A 2 B 3 C 1 D 4.

    Trap to watch: The digit zero is matched with Aryabhata, not the value of pi; in the official key pi goes to Baudhayana and the orbital period to Bhaskaracharya.

    Key facts to recall:

    • The official key pairs the digit zero with Aryabhata.
    • Bhaskaracharya (Bhaskara II) is matched with the time the Earth takes to orbit the Sun.
    • Snakes and ladders is matched with Gyandev (Dnyaneshwar).

    Answer signal: A 2 B 3 C 1 D 4.

  2. UPSC Prelims 1996 GS-IMatch the classical figure in List-I with the field in List-II, where List-II is A. Medicine, B. Drama, C. Astronomy, D. Mathematics. List-I is:
    1. I. Visakhadatta
    2. II. Varahamihira
    3. III. Charaka
    4. IV. Brahmagupta

    Select the correct code:

    1. a I – A, II – C, III – D, IV – B
    2. b I – B, II – A, III – C, IV – D
    3. c I – B, II – C, III – A, IV – D
    4. d I – C, II – B, III – A, IV – B
    How to approach this Prelims question

    Question type: Match-the-list question pairing four classical figures with their fields.

    Approach: Fix the science pairings taught here: Varahamihira to astronomy, Charaka to medicine and Brahmagupta to mathematics; Visakhadatta, the only non-scientist, must then go to drama.

    Trap to watch: Do not give Brahmagupta to astronomy; his fame in this list is for mathematics, while Varahamihira holds astronomy.

    Key facts to recall:

    • Varahamihira is the astronomer (Pancha-Siddhantika).
    • Charaka is the physician (Charaka Samhita).
    • Brahmagupta is the mathematician; Visakhadatta is the dramatist.

    Answer signal: I – B, II – C, III – A, IV – D.

  3. UPSC Prelims 1995 GS-I110. Who among the following anticipated Newton by declaring that all things gravitate to the earth?
    1. a Aryabhata
    2. b Varahamihira
    3. c Buddha Gupta
    4. d Brahmagupta
    How to approach this Prelims question

    Question type: Single-best-answer naming the ancient Indian scholar who anticipated the idea of gravity.

    Approach: Recall that the idea that the Earth attracts bodies to itself belongs to Brahmagupta, who called it the Earth's nature to draw things down.

    Trap to watch: The tempting wrong answer is Aryabhata; the gravity statement is Brahmagupta's, not Aryabhata's.

    Key facts to recall:

    • Brahmagupta described gravity as an attractive force.
    • He said it is the nature of the Earth to attract and keep things.
    • This idea is in his Brahmasphutasiddhanta of 628 CE.

    Answer signal: Brahmagupta.

The Gupta science and mathematics of classical India reached a height so striking that the age is remembered as a golden age of learning. In this period Aryabhata set out the decimal place-value system, gave a fine value for pi, and held that the Earth rotates on its axis; a little later Brahmagupta made the zero a number in its own right and described gravity as an attractive force. Varahamihira gathered the astronomy of the age, while the Ayurvedic classics and the rustless iron pillar show its medicine and its mastery of metal. This part covers the mathematics, the astronomy, the sciences of life and metal, and the exam focus.

The Gupta Golden Age of Science

Why the Gupta Age Became a Golden Age of Learning

What is the significance of the Gupta golden age of science: a long peace, a rich economy and the patronage of kings and monasteries let learning flower as never before in early India.

Political peace under the great Guptas, a settled and prosperous economy, and the support of royal and monastic patrons gave scholars the leisure to think. Sanskrit became the common language of science, so that a discovery made in one place could be read across the land. Ujjain grew into the chief seat of astronomy, and the monastery of Nalanda, founded by Kumaragupta I about 427 CE, became one of the greatest centres of learning in the ancient world.

The Scholars of the Gupta Golden Age in TimeReigns above, lifespans below: the savants lived generations apart, not at one court400 CE450 CE500 CE550 CE600 CE650 CEGupta and post-Gupta reignsChandragupta IIKumaragupta IDecline of the Guptas and the age afterThe navaratna legend’scourt (a later tale)Aryabhata (b. 476, fl. 499)Varahamihira (c. 505 – 587)Brahmagupta (598 – 668)123Key landmarks1Nalanda founded by Kumaragupta I, c. 4272Aryabhata writes the Aryabhatiya, 4993Brahmagupta’s Brahmasphutasiddhanta, 628
Figure 1. The Gupta-age scholars set against the reigns, showing that they lived generations apart and not together at one court.

Distinguishing legend from history: a famous later tale gathers nine gems, the navaratnas, at one royal court, but the great scientists in fact lived generations apart.

Varahamihira lived about 505 to 587 CE, and Brahmagupta from about 598 to 668 CE, while the navaratna legend places them at the court of Chandragupta II, who reigned more than a century earlier. Historians treat the list of nine gems as a much later literary tradition, not a record of any real gathering. The true measure of the age is not a court of nine, but a line of original thinkers stretching across two hundred years.

Aryabhata and the Mathematics of Zero, Pi and Trigonometry

Aryabhata and the Aryabhatiya of 499 CE

What is the significance of Aryabhata's work: a single short book, written by a young man, set the course of Indian mathematics and astronomy for a thousand years.

Born in 476 CE, Aryabhata composed his great work, the Aryabhatiya, in 499 CE, when he was just twenty-three. It is a slim treatise of about a hundred and twenty verses in four parts, the padas, covering the reckoning of time, mathematics, the motions of the heavens and the geometry of the sphere. So compressed is the work that later scholars wrote long commentaries simply to unfold its meaning.

The Four Padas of the AryabhatiyaAryabhata’s slim treatise of 499 CE, in four partsGitikapadaLarge units of time and thetable of sine differences, in13 verses.GanitapadaMathematics: the place-valuesystem, areas and volumes, thevalue of pi, progressions andthe kuttaka, in 33 verses.KalakriyapadaThe reckoning of time and amethod for finding thepositions of the planets, in 25verses.GolapadaThe sphere: the trigonometry ofthe heavens, the cause ofeclipses and the rotation ofthe Earth, in 50 verses.
Figure 2. The four padas (parts) of Aryabhata's Aryabhatiya and what each one covers.

Zero, the Decimal Place-Value System, Pi and Kuttaka

Distinguishing the mathematics: Aryabhata's lasting gift was a way of writing and working with numbers that the whole world would in time adopt.

Aryabhata's numerals rested on a decimal place-value system, in which the worth of a figure depends on its position. He did not yet use a written symbol for zero, but the idea of an empty place was already at work in his method.

For the circle, he gave the ratio that yields pi as about 3.1416, and hinted that its true value can never be written exactly. He drew up the first tables of the sine, and his kuttaka, the pulveriser, solved equations that had long troubled mathematicians.

Table 1. The chief results of Aryabhata and how they stand against modern knowledge.
Aryabhata's result What it was How it stands today
The place-value system Numbers written by position, in tens. The basis of all modern arithmetic.
The value of pi Pi given as about 3.1416, and hinted to be inexact. Correct to four decimal places.
The sine table The first tables of the sine and versine. The foundation of trigonometry.
The rotating Earth The daily turning of the Earth on its axis. A true insight, rare for its age.
The length of the year The year reckoned at about 365.2586 days. Very close to the modern figure.

Astronomy, Varahamihira, Brahmagupta and the Sciences of Life and Metal

The Rotating Earth and the True Cause of Eclipses

What is the significance of Aryabhata's astronomy: he sought natural, geometric causes for what he saw in the sky, in place of the demons of the older sky-lore.

Apparent motion of the stars across the night sky, Aryabhata taught, is not the stars turning about us but the Earth turning on its own axis, a daring thought for his time. He kept, all the same, an earth-centred model of the heavens, with the Sun and Moon carried on circles.

A lunar eclipse occurs, he held, when the Moon enters the shadow of the Earth, and a solar eclipse when the shadow of the Moon falls upon us. In this he gave the true, geometric cause, and rejected the old belief that the demons Rahu and Ketu swallowed the lights of the sky.

How Aryabhata Explained EclipsesBy the shadows of the Earth and the Moon, not by Rahu and KetuThe Sun1Lunar eclipseEarthEarth’s shadowMoon2Solar eclipseMoonMoon’s shadowEarth3What the numbers mean1The Sun is the source of all the light.2Lunar eclipse: the Earth’s shadow fallsupon the Moon.3Solar eclipse: the Moon’s shadow fallsupon the Earth.4Aryabhata gave this true, geometriccause.5He rejected the demons Rahu and Ketu ofthe older sky-lore.45
Figure 3. How Aryabhata explained eclipses by the shadows of the Earth and the Moon, not by Rahu and Ketu.

Varahamihira, Brahmagupta and the Idea of Gravity

Distinguishing the later masters: two great scholars carried the science of the age to its height and a little beyond, in astronomy and in the working of numbers.

A century after Aryabhata, Varahamihira of Ujjain gathered the astronomy of his day in the Pancha-Siddhantika, which set side by side five systems of reckoning, both Indian and Greek; his Brihat Samhita ranged over the whole of natural knowledge.

At the close of the age, Brahmagupta set down in his Brahmasphutasiddhanta of 628 CE the first rules for calculating with the zero and with negative numbers. He also held that gravity is an attractive force, that it is the nature of the Earth to draw things to itself, a thought that anticipated Newton by a thousand years.

From Place-Value to the Number ZeroTwo steps, a century apart, in the Indian idea of zeroAryabhata, 499 CEA decimal place-value system, clearly in placeAn empty place held by a blank, a placeholderHe did NOT yet use a symbol for zeroNumbers written with the letters of the alphabetBrahmagupta, 628 CEThe first rules for arithmetic using zeroZero treated as a number in its own rightRules for negative numbers tooSet down in the Brahmasphutasiddhanta at UjjainThe decimal zero the whole world now uses grew from this Indian line of thought.
Figure 4. From Aryabhata's place-value system to Brahmagupta's rules for zero as a number.

Ayurveda and Metallurgy: Medicine and the Mastery of Metal

What is the significance of the other sciences: beyond number and the heavens, the age cultivated medicine and a mastery of metal that still astonishes.

The Charaka Samhita, on internal medicine, and the Sushruta Samhita, on surgery, are the great classics of Ayurveda; they took shape before the Guptas but were studied and copied in this age, and the Bower Manuscript, in Gupta script, holds the oldest dated fragments of an Indian medical text.

In metal, the age produced the famous rust-resistant iron pillar of Delhi and the Sultanganj Buddha, the largest surviving metal sculpture of the Gupta world, more than two metres tall and cast in pure copper by the lost-wax method.

Table 2. The chief scholars, works and fields of Gupta-age science.
Scholar or work Field What it gave
Aryabhata Mathematics and astronomy The Aryabhatiya: place-value, pi, the sine, the rotating Earth.
Varahamihira Astronomy The Pancha-Siddhantika and the Brihat Samhita.
Brahmagupta Mathematics Rules for zero and negatives; gravity as an attractive force.
Charaka Samhita Medicine The great classic of internal medicine (Ayurveda).
Sushruta Samhita Surgery The great classic of surgery, with its many operations.
The Bower Manuscript Medicine The oldest dated fragments of an Indian medical text.

UPSC Relevance and Exam Focus

Where Gupta-Age Science Fits in the UPSC-CSE Syllabus

This topic belongs to General Studies Paper I: ancient Indian history and culture, and the science, mathematics and astronomy of the Gupta age are a favourite ground for Prelims matching questions.

For Prelims, hold the firm pairings: Aryabhata with the place-value system, the value of pi and the rotation of the Earth; Brahmagupta with the rules for zero and the idea that things gravitate to the Earth; Varahamihira with astronomy; and Charaka with medicine. Note that the famous matching question pairs the digit zero with Aryabhata and gravity with Brahmagupta, not the other way round.

For Mains, Gupta-age science is strong material for an answer on why the period is called a golden age, and on the achievements of ancient Indian science.

Recurring linked concepts an aspirant should keep in working memory:

  • Aryabhata: Place-value, pi as 3.1416, the rotating Earth, eclipses by shadow.
  • The Aryabhatiya: His work of 499 CE, in four padas.
  • Brahmagupta: The first rules for zero; gravity as an attractive force.
  • Varahamihira: The Pancha-Siddhantika and the Brihat Samhita.
  • Ayurveda: Charaka on medicine and Sushruta on surgery.

A common Prelims trap is to credit Aryabhata with heliocentric astronomy or with the formal symbol for zero; he taught the Earth's rotation within an earth-centred model, and the rules for zero as a number came with Brahmagupta in 628 CE. Another swaps Brahmagupta and Aryabhata on the idea of gravity; it was Brahmagupta who said that things gravitate to the Earth.

Prelims MCQ practice

Each question below tests one specific concept on the topic. Click to reveal the answer and a full option-wise explanation.

Q1. With reference to Aryabhata, consider the following statements:

  1. He composed the Aryabhatiya in 499 CE, when he was about twenty-three years old.
  2. He held that the apparent daily motion of the stars is caused by the rotation of the Earth on its axis.

Which of the statements given above is/are correct?

  1. 1 only
  2. 2 only
  3. Both 1 and 2
  4. Neither 1 nor 2
Show answer and explanation

Answer: Both 1 and 2

Explanation.

Both statements are correct. Aryabhata composed the Aryabhatiya in 499 CE at about the age of twenty-three, and he taught that the daily motion of the stars is caused by the Earth's rotation on its axis, though within an earth-centred model. Hence option (c).

Q2. The first rules for calculating with zero as a number, and the statement that the Earth attracts things to itself, are found in the work of which scholar?

  1. Aryabhata
  2. Brahmagupta
  3. Varahamihira
  4. Charaka
Show answer and explanation

Answer: Brahmagupta

Explanation.

Option (b) is correct. Brahmagupta, in his Brahmasphutasiddhanta of 628 CE, gave the first rules for arithmetic with zero and negative numbers and described gravity as an attractive force. Hence option (b).

Q3. The value of pi as approximately 3.1416 was given by which of the following?

  1. Varahamihira
  2. Sushruta
  3. Aryabhata
  4. Brahmagupta
Show answer and explanation

Answer: Aryabhata

Explanation.

Option (c) is correct. Aryabhata, in the Aryabhatiya, gave the ratio that yields pi as about 3.1416 and suggested that the value cannot be written exactly. Hence option (c).

Q4. Which work, composed by Varahamihira, set side by side five systems of astronomical reckoning?

  1. The Brahmasphutasiddhanta
  2. The Pancha-Siddhantika
  3. The Aryabhatiya
  4. The Charaka Samhita
Show answer and explanation

Answer: The Pancha-Siddhantika

Explanation.

Option (b) is correct. Varahamihira's Pancha-Siddhantika summarised five astronomical systems, both Indian and Greek; the Brahmasphutasiddhanta is Brahmagupta's and the Aryabhatiya is Aryabhata's. Hence option (b).

Q5. With reference to medicine in ancient India, consider the following statements:

  1. The Charaka Samhita is a classic of internal medicine.
  2. The Sushruta Samhita is a classic of surgery.

Which of the statements given above is/are correct?

  1. 1 only
  2. 2 only
  3. Both 1 and 2
  4. Neither 1 nor 2
Show answer and explanation

Answer: Both 1 and 2

Explanation.

Both statements are correct. The Charaka Samhita is the great classic of internal medicine and the Sushruta Samhita the great classic of surgery; both are foundational texts of Ayurveda. Hence option (c).

Q6. The great monastery and seat of learning at Nalanda was founded by which Gupta emperor?

  1. Samudragupta
  2. Chandragupta II
  3. Kumaragupta I
  4. Skandagupta
Show answer and explanation

Answer: Kumaragupta I

Explanation.

Option (c) is correct. Nalanda was founded by Kumaragupta I about 427 CE and grew into one of the greatest centres of learning of the ancient world. Hence option (c).

Sources and Further Reading

Editorial Disclaimer

This article is for UPSC preparation. The dates of some ancient scholars are approximate, and the contributions follow the standard accounts of the history of Indian science.