Bissoy.com
Doctors Medicines MCQs Q&A

Noise produced by cooling fans (employed in air cooled heat exchangers or cooling tower) is mainly caused due to the turbulence created by blade passage through air. It can be reduced by use of a slower fan

Noise produced by cooling fans (employed in air cooled heat exchangers or cooling tower) is mainly caused due to the turbulence created by blade passage through air. It can be reduced by use of a slower fan Correct Answer Both A & B

Related Questions

Shikha went to the market to purchase five fans. The cost of the first fan is 25% more than the second fan and price of third fan is 20% less than fourth fan and price of fifth fan is 16% more than price of fourth fan. Price of the fourth fan is 3/4th of the second fan’s price. If the average cost of the first three fans was Rs.35 more than of the last three fans. What is  the cost of the second costliest fan?
Consider the following statements for cooling towers: 1. Cooling tower is an artificial device used to cool the hot cooling water coming out of condenser more effectively. 2. The amount of water usually lost with induced draft cooling tower ranges from 5% to 6% by evaporation. 3. The amount of water usually lost with induced draft cooling tower ranges from 7% to 8% by drift losses. 4. The rate of evaporation of water and its cooling effect on the remaining water depends upon the relative humidity of air passing through the tower. Which of the above statements are correct?
A fan running at a speed of 280 rpm circulates 105 m3/s of air in a mine. If the power input to the motor for driving the fan is recorded to be 75 kW, with the combined efficiency of fan and motor at 70%. If the fan pressure is to be increased by 200 Pa by changing the fan speed. the fan speed in rpm will become
A university library budget committee must reduce exactly five of eight areas of expenditure - I, J, K. L, M, N, O and P - in accordance with the following conditions: If both I and O are reduced, P is also reduced. If L is reduced, neither N nor O is reduced. If M is reduced, J is not reduced. Of the three areas J, K and N exactly two are reduced. If both K and N are reduced, which one of the following is a pair of areas neither of which could be reduced?
A university library budget committee must reduce exactly five of eight areas of expenditure—I, J, K, L, M, N, O and P—in accordance with the following conditions: If both I and O are reduced, P is also reduced.
If L is reduced, neither N nor O is reduced.
If M is reduced, J is not reduced.
Of the three areas J, K, and N exactly two are reduced. Question : If both K and N are reduced, which one of the following is a pair of areas neither of which could be reduced?
In a certain city there are five towers. Tower III is taller than tower II. Height of Tower V is the average of the height of towers I and IV. Height of Tower II is the average of the height of towers I and III. Height of Tower I is the average of the height of towers II and V. Which tower is the shortest?
Below a question is given with one passage and its effects (I) and (II). One of these effects or both or none may be the effect of the statement. Read both the effect and decide which of the following answer choice correctly depicts the relationship between these cause and effect. Passage: In the urban area there exist a lot of industries, commercial places and public places religious places which involve a lot of a  people and working machinery note of sound and when this sound becomes unpleasant it is known as noise. it is one of the reasons why public authorities have divided the city into a number of zones is known as a different noise level. Effects: I        Noise leads to emotional and behavioural stress. A person may feel disturbed in the presence of loud noise such as produced by heating of drums. II       Noise may cause damage to the liver, brain, and heart.  
The fan drift pressure readings and fan quantities are measured to be 500 Pa and 65 m3/s respectively at the time when NVP aids fan pressure. On reversal, the fan delivers a quantity of 50 m3/s while acting against NVP with fan drift pressure of 600 Pa. Assuming that the NVP remains constant in both cases the total resistance of the mine in Ns2/m8 will be
A mine ventilation system consists of two splits A and B with resistances of 0.8 Ns2m-8 and 3.2 Ns2m-8, respectively as shown in figure. Trunk airways have resistance of 0.2 Ns2m-8. The main mine fan is generating pressure of 500 Pa.
Mine Ventilation mcq question image
The flows in the two splits are equalized by placing a booster fan in split B. Assume that the fan pressure does not change after installation of the booster fan. The size of the booster fan in Pa is
Given below are two premises with four conclusions drawn from them. Which of the following conclusions could be validity drawn from the premises? Premises: (i) All fans are tubes (ii) Bulbs are not tubes Conclusions: (A) Fans are not bulbs (B) All tubes are fans (C) Fans are bulbs (D) No tube is bulb Select the correct answer from the options given below: