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Karnataka Board PUCPUC Science Class 11

Estimate the average thermal energy of a helium atom at the temperature on the surface of the Sun (6000 K).

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Question

Estimate the average thermal energy of a helium atom at the temperature on the surface of the Sun (6000 K).

Numerical
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Solution

On the surface of the sun, T = 6000 K

Average thermal energy = `3/2` kT

`= 3/2 xx 1.38 xx 10^(-38) xx 6000`

`= 1.241 xx 10^(-19)` J

Hence, the average thermal energy of a helium atom on the surface of the sun is 1.241 × 10–19 J.

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Chapter 12: Kinetic Theory - Exercises [Page 334]

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NCERT Physics Part 1 and 2 [English] Class 11
Chapter 12 Kinetic Theory
Exercises | Q 7.2 | Page 334

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