A body of weight W is required to move up on rough inclined plane whose angle of inclination with the horizontal is α. The effort applied parallel to the plane is given by(where μ = tanφ = Coefficient of friction between the plane and the body.)

Question: Which of the following refrigerant has the highest freezing point.
[A].

Ammonia

[B].

Carbon dioxide

[C].

Sulphur dioxide

[D].

R-12

Answer: Option B

Explanation:

No answer description available for this question.

Question: In counter-current flow heat exchangers
[A].

both the fluids at inlet are in their hottest state

[B].

both the fluids at inlet are in their coldest state

[C].

both the fluids at exit are in their hottest state

[D].

one fluid is coldest and the other is hottest at inlet

Answer: Option A

Explanation:

No answer description available for this question.

Question: Kirchhoff’s law states that
[A].

the total radiation from a black body per second per unit area is directly proportional to the fourth power of the absolute temperature

[B].

the wave length corresponding to the maximum energy is proportional to the absolute temperature

[C].

the ratio of the emissive power and absorptive power of all bodies is the same and is equal to the emissive power of a perfectly black body

[D].

none of the above

Answer: Option C

Explanation:

No answer description available for this question.

Question: The boiling point of R-12 is about – 30°C.
[A].

True

[B].

False

Answer: Option A

Explanation:

No answer description available for this question.