Q. Dittus-boelter equation is applicable for fluids with phase change.

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Q. Statement 1: Radiation is the transfer of heat by electromagnetic waves.
Statement 2: When heat is radiated from a hot source, the amount of heat received by the body depends on the nature of the body.

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Q. Statement 1: Radiation needs a medium to travel.
Statement 2: Thermal radiation takes place at a certain temperature for every body.

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Q. Statement 1: Radiation is NOT heat.
Statement 2: Maximum value of absorptivity is 1.

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Q. The emission of radiation by any body is independent of the radiation by any body next to it.

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Q. A food industry keeps food cool in a very crude manner, by radiation. It paints its walls white and not black, because of _____

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Q. Which of the following reason does NOT affect radiation between two parallel bodies?

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Q. Freezer is at -18 °C. Will will be Radiative heat transfer if meat is at 298k, its emissivity is 0.82 and average area is 0.045m².
Either use Stefan Boltzmann law or take hᵣ (radiative heat transfer co-efficient) as 0.227.

ε = ( Tₐᵥ/100 )³

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Q. Statement 1: Radiation dryers are used to dry grains and reduce their moisture content before storage.
Statement 2: Baking ovens are used both for making the dough and after that’s made, making biscuits by cutting them and baking them further. This entire process uses radiation.

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Q. In deep freezers, the walls absorb heat from food materials by _____ and keep them cool.

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Q. Radiation dryers use _____

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Q. Which of the following sentences is true?

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Q. If _______ heating has higher heat transfer rates than _______ heating, then why is ________ difficult to be used.

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Q. In a jacketed vessel, the only way to increase the heat transfer rates is to increase the temperature difference.

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Q. Which of the following is an advantage of using pumps as heat transfer equipment?

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Q. External heat exchangers are gaining popularity as they’ve several advantages over conventional methods. Still, there is a major drawback. Which among the following is it?

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Q. Contamination takes place to high extend in Plate heat exchangers.

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Q. Statement 1: In coiled heat exchanger, the coils can be present inside and outside the vessel.
Statement 2: The coils can have either hot/cold fluid present inside them or even electrical coils can be present.

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Q. Which of the following is a parameter to be checked before choosing the shape of the pitch in heat exchangers?

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Q. Statement 1: Difference between 1-1 and 1-2 heat exchanger is that 1-2 has both counter AND co current, whereas 1-1 has only co-current.
Statement 2: 1-2 heat exchanger requires a high pressure drop.

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