Questions and answers for exam Preparation

MCQs

Total Questions : 72 | Page 2 of 8 pages

Question 11. Although microwave heating can be used for drying of food containing uneven water content, it is isn’t done for certain food products like garlic. Why?

No pasteurization
Essential oils being stripped off
None of the mentioned
No pasteurization & Essential oils being stripped off

Discuss Question

Answer: Option D. -> No pasteurization & Essential oils being stripped off
Answer: (d).No pasteurization & Essential oils being stripped off

Question 12. Microwave heating is good for puffed products. Why?

The rate of heat transfer is less than the rate of moisture loss
The heat transfer in these food items takes place so fast that instead of shrinking of the food items due to loss of moisture content, they stay intact and hence puffed
None of the mentioned
All of the mentioned

Discuss Question

Answer: Option B. -> The heat transfer in these food items takes place so fast that instead of shrinking of the food items due to loss of moisture content, they stay intact and hence puffed
Answer: (b).The heat transfer in these food items takes place so fast that instead of shrinking of the food items due to loss of moisture content, they stay intact and hence puffed

Question 13. __________ is when nucleate boiling transforms to film boiling.

Critical temperature
Leiden frost point
Critical temperature & Leiden frost point
None of the mentioned

Discuss Question

Answer: Option B. -> Leiden frost point
Answer: (b).Leiden frost point

Question 14. For a copper pipe, k = 0.3534, temperature difference = 60, B = 0.0125 and A = 850. What is the value of q?

1442 W
1442 kW
1565 W
1565 kW

Discuss Question

Answer: Option B. -> 1442 kW
Answer: (b).1442 kW

Question 15. Which of the following is true about Natural Convection?

Low heat transfer
Due to gravity and natural buoyant forces
Dependent on viscosity, density and thermal conductivity
All of the mentioned

Discuss Question

Answer: Option D. -> All of the mentioned
Answer: (d).All of the mentioned

Question 16. _____ is the equation for unsteady state heat conduction through solid materials.

dT/dx= α (d²T)/ (dt)²
dT/dt= α (d²T)/ (dx)²
dT/dt= α (d²T)/ (dx)²
dT/dt= α (d²T)/ (dt)²

Discuss Question

Answer: Option C. -> dT/dt= α (d²T)/ (dx)²
Answer: (c).dT/dt= α (d²T)/ (dx)²

Question 17. NFo= (αtₜ)/s². Here ‘s’ stands for half slab thickness. Based on this data, ‘s’ for a chapatti/ dosa will be _____

Half slab thickness
Full slab thickness
One and a half slab thickness
Double slab thickness

Discuss Question

Answer: Option B. -> Full slab thickness
Answer: (b).Full slab thickness

Question 18. The reciprocal of heat transfer co-efficient is _____

Conductance
Resistance
Density
Temperature difference

Discuss Question

Answer: Option B. -> Resistance
Answer: (b).Resistance

Question 19. According to Nusselt’s film theory, the film thickness decreases as we move from bottom to top. The heat transfer increases.

True
False
May be True or False
Can't say

Discuss Question

Answer: Option B. -> False
Answer: (b).False

Question 20. Statement 1: Unsteady state heat transfer equation can be used when there is negligible internal resistance.
Statement 2: Unsteady state heat transfer equation can be used for liquid food items which are well stirred, because, temperature gradient within won’t be there.