A body takes 5 minute for cooling from 50⁰C to 40⁰C. Its temperature comes down to 33.33⁰C in next 5 minute. Temperature of surroundings is
Options
(a) 15⁰C (b) 20⁰C (c) 25⁰C (d) 10⁰C
Assuming the sun to have a spherical outer surface of radius r, radiating like a black body at temperature t⁰C, the power received by a unit surface, (normal to the inicident rays) at a distance […]
An ideal black body is equivalent to
Options
(a) Hot sodium lamp (b) Tungsten filament (c) Hot lampblack (d) Small hole in a hollow sphere
Correct Answer:
Small hole in a hollow sphere
Explanation: […]
If the cold junction of a thermo-couple is kept at 0⁰C and the hot junction is kept at T⁰C then the relation between neutral temperature (Tₙ) and temperature of inversion (Ti) is
Options
(a) […]
A body is placed in an insulating container at temperature 227⁰C. In order to keep its temperature at 727⁰C, power of 60 watt is required. Then power required to keep its temperature at 1227⁰C will […]
A body of length 1 m having cross-sectional area 0.75 m² has heat flow through it at the rate of 6000 joule/sec. Then find the temperature difference if K=200 Jm⁻¹K⁻¹
Options
(a) 20⁰C (b) […]
If the interatomic spacing in a steel wire is 3.0 Å and Y of steel is 20×10¹⁰ N/m², then force constant is
Options
(a) 6×10⁻² N/Å (b) 6×10⁻⁹ N/Å (c) 4×10⁻⁵ N/Å (d) 6×10⁻⁵ […]
Which of the following statements is correct?
Options
(a) A good absorber is a bad emitter (b) Every body absorbs and emits radiations at every temperature (c) The energy of radiation emitted from a […]
Which of the following is true for elastic potential energy density?
Options
(a) Energy density=1/2 x strain x stress (b) Energy density= (strain)² x volume (c) Energy density= strain x volume (d) Energy density […]
Which is correct relation?
Options
(a) Y<σ (b) Y>σ (c) Y=σ (d) σ=±1
Correct Answer:
Y>σ
Explanation:
No explanation available. Be the first to write the explanation for this question by commenting below.
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