Sign in
12thPass logo
New chatPYQ LibraryDoubtsRank report
Sign in to see Recents

Your guest activity stays on this device

Sign in to save progress →
Sign in

Properties of Matter question

2009 · Q165
Guest · filters and generic practice availableBrowsing as a guest · PYQ filters and generic practice are available. Sign in only for personalised features and saved progress.
  1. PYQ Library
  2. /NEET
  3. /Physics
  4. /Properties of Matter
  5. /2009 · Q165

Properties of Matter question

2009 · Q165

NEETPhysicsProperties of MatterMCQ+4 / −1
A black body at 227oC radiates heat at the rate of 7 cals/cm2s. At a temperature of 727oC, the rate of heat radiated in the same units will be
  1. A
    50
  2. B
    112
  3. C
    80
  4. D
    60
View written solutionFree

Correct answer: B

Rate of heat radiated at (227 + 273) K = 7 cals/(cm2s)

Let rate of heat radiated at (727 + 273) K = x cals/(cm2s)

By Stefan’s law, 7 ∝\propto∝ (500)4 and x ∝\propto∝ (1000)4

∴\therefore∴ x7=24⇒x=7×24=112 {x \over 7} = {2^4} \Rightarrow x = 7 \times {2^4} = 112\,7x​=24⇒x=7×24=112 cals/(cm2s)

PreviousNext

More from Properties of Matter

  • The two ends of a rod of length L and a uniform cross-sectional area A are Kept at two temperatures T1 and T2 (T1 > T2). The rate of heat transfer, dtdQ​ through the rod in a steady state is given by :2009 · MCQ
  • On a new scale of temperature (which is linear) and called the W scale, the freezing and boiling points of water are 39oW and 239oW respectively. What will be the temperature on the new scale, corresponding to a temperature of 39oC on the…2008 · MCQ
  • Assuming the sun to have a spherical outer surface of radius r, radiating like a black body at temperature toC, the power received by a unit surface, (normal to the incident rays) at a distance R from the centre of the sun is where σ…2007 · MCQ
  • A black body is at 727oC. It emits energy at a rate which is proportional to2007 · MCQ
  • A black body at 1227oC emits radiations with maximum intensity at a wavelength of 5000 A∘​. If the temperature of the body is increased by 1000oC, the maximum intensity will be observed at2006 · MCQ
  • Which of the following rods, (given radius r and length l) each made of the same material and whose ends are maintained at the same temperature will conduct most heat ?2005 · MCQ
  • If λm denotes the wavelength at which the radioactive amission from a black body at a temperature TK is maximum, then2004 · MCQ
  • Consider a compound slab consisting of two different materials having equal thicknesses and thermal conductivities K and 2K, respectively. The equivalent thermal conductivity of the slab is2003 · MCQ