Description : . The inner wall of a furnace is at a temperature of 700°C. The composite wall is made of two substances, 10 and 20 cm thick with thermal conductivities of 0.05 and 0.1 W.m-1.°C-1 respectively. The ambient air is at 30°C ... from the outer surface in W.m-2 is (A) 165.4 (B) 167.5 (C) 172.5 (D) 175
Last Answer : (A) 165.4
Description : A refrigerator is working on reversed carnot cycle between temperature of 30°C to –10°C with capacity of 10 tonnes. Calculate. (i) The COP (ii) Define ton of refrigeration (iii) Give the industrial application of refrigeration
Last Answer : (ii) Ton of refrigeration: It is defined as the quantity of heat required to be removed from 1Ton water at 0oC to get ice at 0oC in one day. (iii) Industrial applications of refrigeration ... food stuff such as meat, fruit, fruit juice, vegetables etc. 5. Ice cooling of concrete for dam.
Description : One face of a furnace wall is at 1030°C and the other face is exposed to room temperature (30°C). If the thermal conductivity of furnace wall is 3 W. m-1. k-1 and the wall thickness is 0.3 m, the maximum heat loss (in W/m) is (A) 100 (B) 900 (C) 9000 (D) 10000
Last Answer : (D) 10000
Description : A thin, flat & square plate measuring 2 m 2 m is freely hanging in ambient air at 25°C. It is exposed to the solar radiation falling on one side of the plate at the rate of 500 W/m2. The plate temperature will ... heat transfer co-efficient is __________ W/m2 °C. (A) 50 (B) 100 (C) 150 (D) 200
Last Answer : (B) 100
Description : The usual energy consumption in electric arc furnace steel making is __________ KWh/ton of steel. (A) 60 - 100 (B) 400 - 700 (C) 1200 -1500 (D) 2000 - 2300
Last Answer : (B) 400 - 700
Description : The heat flux (from outside to inside) across an insulating wall with thermal conductivity, K = 0.04 W/m.°K and thickness 0.16m is 10 W/m2 . The temperature of the inside wall is - 5°C. The outside wall temperature is (A) 25°C (B) 30°C (C) 35°C (D) 40°C
Last Answer : (C) 35°C
Description : 1000 Kg of liquid at 30°C in a well stirred vessel has to be heated to 120°C, using immersed coils carrying condensing steam at 150°C. The area of the steam coils is 1.2 m2 and the overall heat transfer co-efficient to the ... will be (A) 15 min (B) 22 min (C) 44 min (D) 51 min
Last Answer : (D) 51 min
Description : The left face of a one dimensional slab of thickness 0.2 m is maintained at 80°C and the right face is exposed to air at 30°C. The thermal conductivity of the slab is 1.2 W/m.K and the heat transfer co-efficient from the ... temperature of the right face in °C is (A) 77.2 (B) 71.2 (C) 63.8 (D) 48.7
Last Answer : (D) 48.7
Description : Three basic raw materials which are needed in large quantities for production of steel are (A) Iron ore, coal and sulphur (B) Iron ore, carbon and sulphur (C) Iron ore, coal and lime stone (D) Iron ore, carbon and lime stone
Last Answer : Answer: Option C
Description : The wet and 'dry bulb temperature for a vapour-gas mixture are 25°C and 30°C respectively. If the mixture is heated to 45°C at constant pressure, the wet bulb temperature will be __________ °C. (A) 25 (B) > 25 (C) < 25 (D) - 25
Last Answer : (B) > 25
Description : Three materials A, B and C of equal thickness and of thermal conductivity of 20, 40 & 60 kcal/hr. m. °C respectively are joined together. The temperature outside of A and C are 30°C and 100°C respectively. The interface ... C will be at a temperature of __________ °C. (A) 40 (B) 95 (C) 70 (D) 50
Last Answer : (C) 70
Description : Which one among the following substances evolved heat when dissolved in water? (1) Glucose (2) Fructose (3) Quick lime (4) Salt peter
Last Answer : (3) Quick lime Explanation: Quicklime is a widely used chemical compound. It is a white, caustic, alkaline, crystalline solid at room temperature. When limestone is heated, at about 1000° C it undergoes thermal decomposition.
Description : Concentrated HCl at 30°C can be stored in a vessel made of (A) PTFE and porcelain (B) Cast iron and aluminium (C) Stainless steel and high silicon cast iron (D) None of these
Last Answer : (A) PTFE and porcelain
Description : 100% H2SO4 at 30°C can't be stored in a vessel made/lined with (A) Cast iron and high silicon iron (B) Mild steel and stainless steel (C) Aluminium, tin and rubber (D) Teflon, glass and porcelain
Last Answer : (C) Aluminium, tin and rubber
Description : Pick out the wrong statement. (A) A refrigeration cycle violates the second law of thermodynamics (B) Refrigeration cycle is normally represented by a temperature vs. entropy plot (C) In a refrigerator, ... (D) One ton of refrigeration is equivalent to the rate of heat absorption equal to 3.53 kW
Last Answer : (A) A refrigeration cycle violates the second law of thermodynamics
Description : Optimum temperature for maximum crop development in wheat is (a) 10-15°C(b) 20-25°C (c) 25-30°C (d) 30-35°C
Last Answer : (b) 20-25°C
Description : Pick out the wrong statement. (A) LPG is also used as fuel for automobiles & small furnaces and for cutting & welding of metals (B) The minimum temperature, at which a petroleum oil vapor catches ... about 30-50 Nm3 of gas (D) Maximum yield of naphthalene is obtained on distillation of crude oil
Last Answer : (B) The minimum temperature, at which a petroleum oil vapor catches fire and continues to burn, is called its flash point
Description : Yield of coke oven gas in low temperature carbonisation of coal is about __________ Nm3 /ton of dry coal. (A) 60 (B) 160 (C) 500 (D) 750
Last Answer : (B) 160
Description : Quantity of coke oven gas produced by high temperature carbonisation of one ton of dry coal may be around __________ Nm3 . (A) 30 (B) 300 (C) 3,000 (D) 30,000
Last Answer : (B) 300
Description : A 10 cm dia steam pipe, carrying steam at 180°C, is covered with an insulation (conductivity = 0.6 W/m.°C). It losses heat to the surroundings at 30°C. Assume a heat transfer co-efficient of 0 ... that of the un-insulated steam pipe (D) Less than the steam pipe with 5 cms insulation
Last Answer : (B) Less than that of the un-insulated steam pipe
Description : It is desired to concentrate a 20% salt solution (20 kg of salt in 100 kg of solution) to a 30% salt solution in an evaporator. Consider a feed of 300 kg/min at 30°C. The boiling point of the solution is 110°C, the latent heat of ... 3.06 10 5 (B) 6.12 10 5 (C) 7.24 10 5 (D) 9.08 10
Last Answer : (A) 3.06 × 10
Description : Pick up the correct statement from the following: (A) The free quartz suddenly expands at a temperature lower than 600°C (B) The lime stone resists fire upto about 800°C and at higher temperature it splits into ... (C) The sand stone with silicates resist a fire in a better way (D) All the above
Last Answer : Answer: Option D
Description : Pick out the correct statement. (A) Higher is the temperature of the radiating body, higher is the wavelength of radiation (B) Logarithmic mean area is used for calculating the heat flow rate ... ) Solid angle subtended by the finite surface at the radiating element is called the angle of incidence
Last Answer : (B) Logarithmic mean area is used for calculating the heat flow rate through a thick walled cylinder
Description : The main problem with such a heat treatment of stainless steel pipe spools and the reason why it is not regularly employed is: a) Controlling the rate of the temperature rise b) Controlling the cooling c) The length of the soak period d) High risk of distortion
Last Answer : d) High risk of distortion
Description : __________ is the most suitable lubricant for drawing mild steel wires? (A) Kerosene (B) Water (C) Sodium stearate (D) Lime water
Last Answer : (C) Sodium stearate
Description : A mixture of 10% C6H6 vapour in air at 25°C and 750 mm Hg has a dew point of 20°C. Its dew point at 30°C and 700 mm Hg will be around __________ °C. (A) 21.7 (B) 20 (C) 27.3 (D) 18.7
Last Answer : (D) 18.7
Description : A stone of wight 100 kg is thrown vertically upwards by a man of height y = 1.8 m with an initial velocity of 20 m/sec. The maximum height to which it will rise would be a.22.2 m b.26 m c.15.1 m d.20.2 m e.10 m
Last Answer : a. 22.2 m
Description : Air initially at 101. 3 kPa and 40°C and with a relative humidity of 50%, is cooled at constant pressure to 30°C. The cooled air has a (A) Higher dew point (B) Higher absolute (specific) humidity (C) Higher relative humidity (D) Higher wet bulb temperature
Last Answer : (C) Higher relative humidity
Description : Heating the Hypo-eutectoid steels to 30°C above the upper critical temperature line, soaking at that temperature and then cooling slowly to the room temperature to form a pearlite & ferrite structure is called (A) Tempering (B) Hardening (C) Annealing (D) Normalising
Last Answer : Option C
Description : One ton of refrigeration capacity is equivalent to the heat removal rate of (A) 50 kcal/hr (B) 200 BTU/hr (C) 200 BTU/minute
Last Answer : (C) 200 BTU/minute
Description : One ton of refrigeration is not equivalent to the heat removal rate of (A) 200 BTU/minute (B) 50 kcal/minute (C) 50 kJ/sec (D) 3.5 KW
Last Answer : (C) 50 kJ/sec
Description : The cooling rate required to freeze 1 ton of water at 0°C into ice at 0°C in 24 hours is __________ BTU/hr. (A) 100 (B) 200 (C) 1000 (D) 2000
Last Answer : (B) 200
Description : In a 100 TPD Sponge Iron plant, the sponge iron is fed to the Induction melting furnace, producing molten steel at 88% yield. The Energy consumption details are as follows: Coal Consumption : 130 ... molten steel (product). 3. Total Energy Consumption of Plant in Tons of Oil Equivalent (TOE )
Last Answer : a) Specific Energy Consumption of Induction Melting Furnace Molten Steel Production from the Induction melting furnace per day = 100 x 88/100 = 88 TPD Total Energy Consumption of the Plant = 82400 kWh ... mark c) Total Energy consumption of Plant in ToE = 655864000/107 = 65.586 ToE
Description : Adiabatic compression is one in which A. Temperature during compression remains constant B. No heat leaves or enters the compressor cylinder during compression C. Temperature rise follows a linear relationship D. Work done is maximum.
Last Answer : ANSWER : B
Description : One item listed on the name plate of a cargo pump motor is 'degrees centigrade rise.' This number is based on _____________. A. normal temperature change from cold to hot B. an ambient temperature ... . minimum heat rise from no load to full load D. maximum degrees centigrade rise from absolute zero
Last Answer : Answer: B
Description : Maximum heat dissipation occurs from a steel wire (k = 0.5 W/m. k) of 15 mm diameter exposed to air (h = 20W/m2.k), when the insulation thickness is __________ mm. (A) 15 (B) 25 (C) 10 (D) 30
Last Answer : (B) 25
Description : What happens when the temperature of water falls from 30°C and 0°C? (a) The volume of ice formed will be less than volume of water (b) The volume of ice formed will be more than the volume of water (c) Water will not freeze at 0°C (d) None of the above
Last Answer : Ans:(b)
Description : According to the Indian Standards the specific gravity is the ratio of the unit weight of soil solids to that of water at a temperature of (A) 17°C (B) 23°C (C) 27°C (D) 30°C
Last Answer : (C) 27°C
Description : __________ glass has the lowest co-efficient of thermal expansion and hence is more heat resistant. (A) Pyrex (B) Soda lime (C) Lead (D) High silica
Last Answer : (A) Pyrex
Description : The difference between total carbon and fixed carbon of coal will be minimum in case of (A) Lignite (B) Bituminous coal (C) Anthracite (D) High temperature coke (V.M < 0.5%)
Last Answer : (D) High temperature coke (V.M < 0.5%)
Description : Ignition temperature decreases progressively from anthracite to lignite, because (A) Volatile matter content increases (B) Carbon content decreases (C) Moisture content increases (D) Ash content increases
Last Answer : (A) Volatile matter content increases
Description : Energy consumed for crushing one ton of material ranges from __________ kWh. (A) 0.01 to 0.1 (B) 0.5 to 1.5 (C) 2 to 3.5 (D) 4 to 5
Last Answer : (B) 0.5 to 1.5
Description : Yield of blast furnace gas is about __________ Nm3 /ton of pig iron. (A) 300 (B) 2000 (C) 5000 (D) 10000
Last Answer : (B) 2000
Description : Gas yield in the Kopper-Totzek coal gasifier is about __________ Nm3 /ton coal (ash = 35%). (A) 150 (B) 1500 (C) 3500 (D) 5000
Last Answer : (C) 3500
Description : Production of one ton of dry paper pulp requires about __________ tons of bamboo or wood. (A) 1 (B) 2.5 (C) 5 (D) 10
Last Answer : (B) 2.5
Description : Production of one ton of cement requires about __________ tons of limestone. (A) 0.6 (B) 1.2 (C) 2.2 (D) 3.8
Last Answer : (B) 1.2
Description : Production of one ton of paper in Indian paper industry consumes about __________ kWh of electricity. (A) 300 (B) 800 (C) 1400 (D) 2000
Last Answer : (C) 1400
Description : Which stone floats on water? A. Pumice stone (Answer) B. Lime stone C. Basalt stone D. Quartzite stone
Last Answer : A. Pumice stone (Answer)
Description : Pavement is said to be flexible if it contains (A) Water bound macadam surface (B) Stabilised soil base constructed of lime cement or tar (C) Bitumen-bound stone layer of varying aggregates (D) All the above
Description : Hydraulic lime is obtained by (A) Burning of lime stone (B) Burning of kankar (C) Adding water to quick lime (D) Calcination of pure clay
Last Answer : Answer: Option B