Q27.Two spheres of the same material have radii 1 m and 4 m and temperatures 4000 K and 2000 K respectively. The ratio of the energy radiated per second by the first sphere to that by the second is (1) 1 : 1 (2) 16 : 1 (3) 4 : 1 (4) 5 : 3
What This Question Tests
This question requires applying the Stefan-Boltzmann law to calculate the ratio of energy radiated per second by two spheres with different radii and temperatures, assuming they are made of the same material (same emissivity).
Concepts Tested
Formulas Used
P = σAeT⁴
📚 NCERT Sections This Tests
2.4 — A Spherical Conductor Of Radius 12 Cm Has A Charge Of 1.6 × 10–7C
Physics Class 11 · Chapter 2
2.4 A spherical conductor of radius 12 cm has a charge of 1.6 × 10–7C distributed uniformly on its surface. What is the electric field (a) inside the sphere (b) just outside the sphere (c) at a point 18 cm from the centre of the sphere?
12.7 — The Radius Of The Innermost Electron Orbit Of A Hydrogen Atom Is
Physics Class 12 · Chapter 12
12.7 The radius of the innermost electron orbit of a hydrogen atom is 5.3×10–11 m. What are the radii of the n = 2 and n =3 orbits?
13.4 — Obtain Approximately The Ratio Of The Nuclear Radii Of The Gold Isotope
Physics Class 12 · Chapter 13
13.4 Obtain approximately the ratio of the nuclear radii of the gold isotope 197 79 Au and the silver isotope 10747 Ag .
📋 Question Details
- Chapter
- Thermodynamics & KTG
- Topic
- Stefan-Boltzmann Law
- Year
- 2002
- Shift
- Unknown
- Q Number
- Q27
- Type
- MCQ
- NCERT Ref
- Class 11 Physics Ch 11: Thermal Properties of Matter
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