1 Answer

Answer :

" Black" material has high heat absorption capacity.

Related questions

Last Answer : : The heat absorption capacity of an object depends on the color.

Description : The reason why materials appear colored is (a) The selective absorption of spectral colors (b) The interaction between the light and the electrons of the dye molecules (c) The composition of the white light from various spectral colors (d) All of these

Last Answer : All of these

Description : Absorption accompanied by heat evolution results in (A) Increased capacity of the absorber (B) Increase in equilibrium solubility (C) Decrease in equilibrium solubility (D) None of these

Last Answer : (C) Decrease in equilibrium solubility

Description : What refers to the amount of heat needed to raise the temperature of an object by one degree Celsius or 1K?  A. Heat capacity  B. Specific heat  C. Latent heat  D. Molar heat

Last Answer : Heat capacity

Description : On a cold day when the room temperature is 15°C, the metallic cap of a pen becomes much colder than its plastic body, though both are at the same temperature of 15°C, because - (1) metals ... metals (3) metals are good conductors of heat (4) plastics have a higher thermal conductivity than metals

Last Answer : (3) metals are good conductors of heat Explanation: On a chilly day, the room temperature is lower than our body temperature. Since metals have a higher coefficient of thermal conductivity than plastic, they ... from our fingers will flow to the metal cap much more quickly than to the plastic body.

Description : A multiple effect evaporator as compared to a single effect evaporator of the same capacity has (A) Lower heat transfer area (B) Lower steam economy (C) Higher steam economy (D) Higher solute concentration in the product

Last Answer : (C) Higher steam economy

Description : Glycerine is used as a coolant in cooling of some engines instead of water, because (A) Its higher boiling point (290°C) increases its heat carrying capacity (B) Comparatively less weight of coolant is required (C) Smaller radiator can be used (D) All a, b & c

Last Answer : (D) All a, b & c

Description : On a cold day when the room temperature is 15°C, the metallic cap of a pen becomes much colder than its plastic body, though both are at the same temperature of 15°C, because : (1) metals ... metals (3) metals are good conductors of heat (4) plastics have a higher thermal conductivity than metals

Last Answer : metals are good conductors of heat

Description : Does heat energy flow from an object at a higher temperature to an object at a lower temperature?

Last Answer : Yes, this happens spontaneously. It actually flows both ways,but the hotter object loses energy faster, so the system will tryto reach equilibrium.

Description : The energy that flows from higher temperature object to a lower temperature object because of the difference in temperature is called  a. heat  b. temperature  c. thermodynamics cycle  d. energy flow

Last Answer : heat

Description : Sparking at the brushes of a running motor could be an indication of _____________. A. normal operation B. a dirty commutator C. increased brush capacity D. water vapor absorption

Last Answer : Answer: B

Description : Pick out the wrong statement. (A) Denier is defined as weight in gm of 9000 metres length of a fibre, while tex is defined as weight in gm of 1000 metres length of fibre (B) ... fibres are all prepared by wet spinning (D) Nylon fibres have greater water absorption capacity than polyester fibres

Last Answer : (C) Dacron fibres, acrylic fibres, viscose rayon fibres & cellulose acetate fibres are all prepared by wet spinning

Description : Nylon-6, 10 which is used for bristles making is superior to nylon 6, 6 due to its lower water absorption capacity, is a/an (A) Polyester (B) Polyamide (C) Polyisopren

Last Answer : (B) Polyamide

Description : Slate (A) Is a metamorphic rock (B) Splits into thin sheets along its bedding planes (C) Has a smooth surface and contains alumina and silica (D) Possesses good water absorption capacity

Last Answer : Answer: Option A

Description : The following is true of aluminium hydroxide gel except: A. It is a weak and slowly reacting antacid B. Its acid neutralizing capacity decreases on storage C. It interferes with absorption of phosphate in the intestine D. It causes loose motions as a side effect

Last Answer : D. It causes loose motions as a side effec

Description : According to Bohr's theory, an electron in one Bohr stationary orbit can go to a higher stationary orbit (a) By emission of electromagnetic radiation (b) Without any absorption ... absorption of any electromagnetic radiation (d) With absorption of electromagnetic radiation of a particular frequency

Last Answer : Ans:(d)

Description : When a metal is heated in a flame, the electrons absorb energy and jump to higher energy state. On coming back to the lower energy state, they emit light, which we can observe in - (1) Raman spectra (2) Absorption spectra (3) Emission spectra (4) Fluorescence

Last Answer : (3) Emission spectra Explanation: When a metal atom is strongly heated, its electrons absorb the heat energy and jump to a higher energy level. When the electron returns to its original position it ... to the energy the electron has released at each stage °fits fall back to its original state.

Description : Pick out the correct statement. (A) Higher hold up of the solid in the rotary dryer results in better exposure of the solids to the gas (B) The 'Hatta number' is ... reflux in case of distillation operation requires infinite number of plates for a binary system separation

Last Answer : (C) For a non-reacting binary mixture of ideal gases, the partial pressure distribution of both components is linear in the case of steady state equimolal counter-diffusion

Description : When a metal is heated in a flame, the electrons absorb energy and jump to higher energy state. On coming back to the lower energy siate, they emit light, which we can observe in (1) Raman spectra (2) Absorption spectra (3) Emission spectra (4) Fluorescence

Last Answer : Emission spectra

Description : In the blast furncae the reaction that occurs in the zone of heat absorption is

Last Answer : In the blast furncae the reaction that occurs in the zone of heat absorption is A. `CO_(2)+C to 2CO` B. ` ... CO_(2)` D. `FeO+SiO_(2) to FeSiO_(3)`

Description : The evolution of heat of solution takes place in ammonia absorption plant when (a) ammonia vapour goes into solution (b) ammonia vapour is driven out of solution (c) lithium bromide mixes with ammonia (d) weak solution mixes with strong solution

Last Answer : Ans: a

Description : Choose the wrong statement (a) Temperature of medium being cooled must be below that of the evaporator (b) Refrigerant leaves the condenser as liquid (c) All solar thermally operated absorption systems are capable only of intermittent operation (d) frost on evaporator reduces heat transfer

Last Answer : Ans: a

Description : Pick up the correct statement about giving up of heat from one medium to other in ammonia absorption system (a) strong solution to weak solution (b) weak solution to strong solution (c) strong solution to ammonia vapour (d) ammonia vapour to strong solution.

Last Answer : Ans: b

Description : Which of the following is most important for absorption of heat radiated from the Sun as well as from the Earth? (1) Carbon dioxide (2) Oxygen (3) Carbon monoxide (4) Nitrogen

Last Answer : (1) Carbon dioxide Explanation: Carbon dioxide is a green house gas that absorbs heat radiated from the Sun as well as re-radiated heat from the Earth's surface.

Description : Heat transfer horizontally within the atmosphere is called – (1) Conduction (2) Convection (3) Absorption (4) Advection

Last Answer : (4) Advection Explanation: Convection transfers heat vertically into the atmosphere. In order for heat to be transferred to other regions, it must be transferred horizontally by the wind. The horizontal ... advection is the transport of pollutants or silt in a river by bulk water flow downstream.

Description : Heat is generated in a nuclear reactor (thermal) by (A) Combustion of a nuclear fuel e.g. uranium (B) Fusion of atoms of uranium (C) Absorption of neutrons in uranium atoms (D) Fission of U-235 by neutrons

Last Answer : (D) Fission of U-235 by neutrons

Description : Physical absorption is (A) An irreversible phenomenon (B) A reversible phenomenon (C) Accompanied by evolution of heat (D) Both (B) and (C)

Last Answer : (D) Both (B) and (C)

Description : Low viscosity absorbent is preferred for reasons of (A) Rapid absorption rates and good heat transfer characteristics (B) Improved flooding characteristics (C) Low pressure drop on pumping (D) All (A), (B) and (C)

Last Answer : (D) All (A), (B) and (C)

Description : Heat sensitive materials with very high latent heat of vaporisation may be economically separated using (A) Liquid extraction (B) Distillation (C) Evaporation (D) Absorption

Last Answer : (A) Liquid extraction

Description : Absorption (liquid-gas system) with evolution of heat as compared to isothermal absorption results in (A) Decreased solute solubility (B) Large minimum liquid to gas (L/G) ratio (C) Large number of trays (D) All (A), (B) and (C)

Last Answer : (D) All (A), (B) and (C)

Description : A chemical reaction in which there is absorption of heat is called

Last Answer : endothermic reaction.

Description : The atmosphere near the earth's surface is heated from below. Which of the following does not significantly contribute to this heating -----------? A. Conduction of heat upward from a ... infrared energy that has been radiated from the surface D. Heat energy from the earth's interior (Answer)

Last Answer : D. Heat energy from the earth’s interior (Answer)

Description : The Graetz number is concerned with the (A) Mass transfer between a gas and a liquid (B) Absorption with chemical reaction (C) Heat transfer in turbulent flow (D) Heat transfer in laminar flow

Last Answer : (D) Heat transfer in laminar flow

Description : Choose the best definition of dielectric loss. a) Absorption of electric energy by dielectric in an AC field b) Dissipation of electric energy by dielectric in a static field c) Dissipation of heat by dielectric d) Product of loss tangent and relative permittivity

Last Answer : a) Absorption of electric energy by dielectric in an AC field

Description : Pick out the correct statement. (A) A chemical reaction accompanied by absorption of heat is called an exothermic reaction (B) A chemical reaction accompanied by evolution of heat is called an ... does not change on changing the concentration units (D) Chemical equilibrium state is dynamic in nature

Last Answer : (C) The rate constant for a first order reaction does not change on changing the concentration units

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 : Absorption/evolution of heat during conversion of a substance from one allotropic form to another is termed as the heat of (A) Sublimation (B) Fusion (C) Transition (D) Vaporisation

Last Answer : C) Transition

Description : Cooling tower is a ______device a) Heat absorption b) heat rejection c) Both a and b c) neither a nor b

Last Answer : heat rejection

Description : The relative heat absorption for successively added equal areas of boiler convection heating surfaces__________ (A) Increases (B) Decreases (C) Remain unaffected (D) First increases and then decreases

Last Answer : (B) Decreases

Description : It is analogous to power dissipation to copper cables, impurities in the fiber absorb the light and covert it to heat. ∙ A. power loss ∙ B. absorption loss ∙ C. resistive loss ∙ D. heat loss

Last Answer : B. absorption loss

Description : Results in reduction in the power of light wave as it travels down the cable. ∙ A. power loss ∙ B. absorption loss ∙ C. resistive loss ∙ D. heat loss

Last Answer : A. power loss

Description : What is the name of the phenomenon that causes an accumulation of heat in the lower atmosphere because of the absorption of longwave radiation from the Earth's surface?

Last Answer : ANSWER: GREENHOUSE EFFECT

Description : Heat transfer horizontally within the atmosphere is called (1) Conduction (2) Convection (3) Absorption (4) Advection

Last Answer : Advection

Description : For the same capacity engines, the compression ratio of diesel engine a. is lower than the compression ratio of SI engine b. is higher than the compression ratio of SI engine c. is same as the compression ratio of SI engine d. cannot say

Last Answer : ANSWER b. is higher than the compression ratio of SI engine

Description : A backward feed multiple effect evaporator is better than forward feed for concentrating cold feed, because it provides (A) Higher economy (B) Lower capacity (C) Both (A) & (B) (D) Lower economy

Last Answer : (A) Higher economy

Description : What is the main advantage of hydrodynamic bearing over roller bearing? (a) Easy to assemble [IES-2005] (b) Relatively low price (c) Superior load carrying capacity at higher speeds (d) Less frictional resistance

Last Answer : (c) Superior load carrying capacity at higher speeds

Description : Fqra cold viscous feed, backward feed gives __________ than forward feed. (A) A higher capacity (B) A lower capacity (C) Lower economy (D) None of these

Last Answer : (A) A higher capacity

Description : The advantage of a concrete pile over a timber pile, is (A) No decay due to termites (B) No restriction on length (C) Higher bearing capacity (D) All the above

Last Answer : Answer: Option D

Description : TIG welding, thoriated tungsten electrodes are used, because it (A) Has higher current carrying capacity (B) Has better electron emissivity (C) Is stronger than ordinary tungsten (D) Is easy to prepare

Last Answer : Option B