Skip to content
Login Register

#science

28 public questions tagged with this topic.

PHYSICS

What is the approximate mass number of a nucleus with radius 4.8 × 10⁻¹⁵ m ? (Given R_0 = 1.2 × 10⁻¹⁵ m )

Given: What is the approximate mass number of a nucleus with radius 4.8 × 10⁻¹⁵ m ? (Given R_0 = 1.2 × 10⁻¹⁵ m ) These values define the system as per NCERT data. Formula: R = R_0 A^{1/3. This is the standard NCERT relation for this phenomenon. Substitution & Calculation: 4.8 × 10⁻¹⁵= 1.2 × 10⁻¹⁵ × A^{1/3 . A^{1/3 = 4.8/1.2 = 4 . A = 4³ = 64 . Result: The computed value matches the expected outcome and confirms the correct choice. Units and powers like J kg⁻¹ K⁻¹, m/s², 10⁻⁵ are properly used as per NCERT.

Ref: NCERT Physics Textbook for Class XI and XII, Chapter: Dual Nature, Atoms, Nuclei and Electronic Devices, Topic: Atomic structure, nuclear binding and semiconductor physics.

View Details
ZOOLOGY

Which of the following statements about fishes is correct?

Cartilaginous fishes lack an operculum and instead have gill slits for respiration. This follows from NCERT principle where relation explains outcome clearly for students.

Ref: NCERT Biology Textbook for Class XI and XII (Zoology section), Chapter: Animal Kingdom, Topic: Chondrichthyes, cartilaginous skeleton, absence of swim bladder, placoid scales.

View Details
ZOOLOGY

Which of the following statements about enzymes is incorrect?

Enzymes are not consumed in reactions; they remain unchanged and can be reused. This follows from NCERT principle where relation explains outcome clearly for students.

Ref: NCERT Biology Textbook for Class XI and XII (Zoology section), Chapter: Biology - Zoology portion covering relevant system and function, Topic: Structural organization and physiology.

View Details
ZOOLOGY

Which of the following statements about enzymes is incorrect?

Enzymes are not consumed in reactions; they remain unchanged and can be reused. This follows from NCERT principle where relation explains outcome clearly for students.

Ref: NCERT Biology Textbook for Class XI and XII (Zoology section), Chapter: Biology - Zoology portion covering relevant system and function, Topic: Structural organization and physiology.

View Details
CHEMISTRY

What is the SI unit of frequency?

Frequency, the number of waves passing a point per second, is measured in hertz (Hz), where 1 Hz = 1 s^{-1. This follows from NCERT principle where the relation explains the outcome clearly for students in simple steps.

Ref: NCERT Chemistry Textbook for Class XI and XII, Chapter: Some Basic Concepts, Structure of Atom and Periodicity, Topic: Mole concept, atomic models and periodic trends.

View Details
PHYSICS

Which of the following devices uses microwaves to heat food?

Microwave ovens use microwaves to match the resonant frequency of water molecules, heating food effectively. This follows from NCERT principle where the relation explains the outcome clearly for students in simple steps.

Ref: NCERT Physics Textbook for Class XI and XII, Chapter: Oscillations and Waves, Topic: SHM, wave motion and superposition.

View Details