Practice questions

General Science practice questions (Group 4)

Questions 1 to 7 of 20

By TNPSC Guide editorial team · Last updated: 27.10.2026

1. Question 1

   Assertion [A]: Vehicles are fitted with springs and shock absorbers. Reason [R]: When the time of impact increases, the impulsive force decreases.

   1. A. [A] is true but [R] is false
   2. B. Both [A] and [R] are true and [R] is the correct explanation of [A]
   3. C. [A] is false but [R] is true
   4. D. Both [A] and [R] are true but [R] is not the correct explanation of [A]
   Answer and explanation

   Correct answer: B. Both [A] and [R] are true and [R] is the correct explanation of [A]

   A longer time of impact lowers the impulsive force, which is why vehicles have springs and shock absorbers; [R] explains [A].

   Source: அறிவியல், பத்தாம் வகுப்பு, தமிழ் வழி (Science, Standard X, Tamil medium; Samacheer Kalvi) (அலகு 1 இயக்க விதிகள், p. 7 (PDF p. 15))

2. Question 2

   Which of the following is not one of the types of inertia the textbook names?

   1. A. Inertia of mass
   2. B. Inertia of rest
   3. C. Inertia of motion
   4. D. Inertia of direction
   Answer and explanation

   Correct answer: A. Inertia of mass

   Inertia is of three types, of rest, of motion and of direction; 'inertia of mass' is not one of them.

   Source: அறிவியல், பத்தாம் வகுப்பு, தமிழ் வழி (Science, Standard X, Tamil medium; Samacheer Kalvi) (அலகு 1 இயக்க விதிகள், p. 11 (PDF p. 19))

3. Question 3

   Which quantity equals the product of the mass and the velocity of a moving body?

   1. A. Impulse
   2. B. Weight
   3. C. Inertia
   4. D. Momentum
   Answer and explanation

   Correct answer: D. Momentum

   Momentum = mass × velocity of the moving body.

   Source: அறிவியல், பத்தாம் வகுப்பு, தமிழ் வழி (Science, Standard X, Tamil medium; Samacheer Kalvi) (அலகு 1 இயக்க விதிகள், p. 11 (PDF p. 19))

4. Question 4

   Flying of a bird, swimming and the backward movement of a gun are examples of which of Newton's laws of motion?

   1. A. The first law of motion
   2. B. The second law of motion
   3. C. The third law of motion
   4. D. The law of gravitation
   Answer and explanation

   Correct answer: C. The third law of motion

   Flying, swimming and the recoil of a gun illustrate the third law: every force has an equal and opposite force.

   Source: அறிவியல், பத்தாம் வகுப்பு, தமிழ் வழி (Science, Standard X, Tamil medium; Samacheer Kalvi) (அலகு 1 இயக்க விதிகள், p. 7 (PDF p. 15))

5. Question 5

   Which of the following is an example of isotones?

   1. A. ₆C¹³, ₇N¹⁴
   2. B. ₁₇Cl³⁵, ₁₇Cl³⁷
   3. C. ₁₈Ar⁴⁰, ₂₀Ca⁴⁰
   4. D. ₇N¹⁴, ₁₇Cl³⁵
   Answer and explanation

   Correct answer: A. ₆C¹³, ₇N¹⁴

   Isotones have the same number of neutrons: ₆C¹³ has 13 − 6 = 7 and ₇N¹⁴ has 14 − 7 = 7.

   Source: அறிவியல், பத்தாம் வகுப்பு, தமிழ் வழி (Science, Standard X, Tamil medium; Samacheer Kalvi) (அலகு 7 அணுக்களும் மூலக்கூறுகளும், p. 101 (PDF p. 109))

6. Question 6

   According to the textbook, what is the value of the Avogadro number?

   1. A. 6.023 × 10²³
   2. B. 6.023 × 10⁻²³
   3. C. 22.4
   4. D. 273.15
   Answer and explanation

   Correct answer: A. 6.023 × 10²³

   The Avogadro number, named after the Italian scientist Avogadro, is 6.023 × 10²³.

   Source: அறிவியல், பத்தாம் வகுப்பு, தமிழ் வழி (Science, Standard X, Tamil medium; Samacheer Kalvi) (அலகு 7 அணுக்களும் மூலக்கூறுகளும், p. 96 (PDF p. 104))

7. Question 7

   By the modern periodic law, the physical and chemical properties of elements depend on what?

   1. A. Atomic mass
   2. B. Number of neutrons
   3. C. Vapour density
   4. D. Atomic number
   Answer and explanation

   Correct answer: D. Atomic number

   The modern periodic law: the physical and chemical properties of elements depend on their atomic numbers.

   Source: அறிவியல், பத்தாம் வகுப்பு, தமிழ் வழி (Science, Standard X, Tamil medium; Samacheer Kalvi) (அலகு 8 தனிமங்களின் ஆவர்த்தன வகைப்பாடு, p. 105 (PDF p. 113))