Answer:

Explanation:
Given that,
Efficiency of heat engine, 
Temperature of hot source, 
We need to find the temperature of cold sink i.e.
. The efficiency of heat engine is given by :




So, the temperature of the cold sink is 256.2°C. Hence, this is the required solution.
Answer:
When a man travels from Hilly region to Terai region, his weight gradually increases because the value of g is more at the Terai region than that in hilly region. 3. An object weights 20 N in air and 16 N in liquid, then answer the following questions.
Explanation:
because the value of g is more at the Terai region than that in hilly region. 3. An object weights 20 N in air and 16 N in liquid, then answer the following questions.
The force is reasonable for making fusion possible in the Sun is heat energy.
<h3>What is nuclear fission and fusion?</h3>
When the slow moving neutrons are bombarded with the heavy radioactive nuclei, the product is the more number of neutrons are produced with the large amount of energy. This multiplying process is called nuclear fusion.
The amount of energy produced in such a reaction can be calculated using the equivalence of mass and energy relationship.
E = mc²
The same happens in nuclear fusion where large amount of energy is needed to make more heavy nuclei.
Thus, fusion requires heat energy to continue the reaction.
Learn more about nuclear fusion and fission.
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