Description : The water in an open pond remains cool even in hot summer because (a) Of continuous evaporation of water (b) Water radiates heat more rapidly than the atmosphere (c) Water absorbs heat less rapidly than the atmosphere (d) Water absorbs heat more rapidly than the atmosphere
Last Answer : Ans:(c)
Description : Which one of the following is the most possible solution for planning improvement of a metropolitan city in India? [IAS 2003] (a) Constructing high rise building and sky scrapers (b) ... and satellite towns around the main city (d) Preventing immigration of people into the metropolitan city
Last Answer : Ans: (b)
Description : Agglomeration of individual particles into clusters (flocs) is called flocculation. To prevent flocculation, the most commonly used dispersing agents are (A) Carbonates (B) Sulphates (C) Silicates & phosphates (D) Bi-carbonates
Last Answer : (C) Silicates & phosphates
Description : I'm an object; good at drawing. I draws without using any drawing instrument, yet I can draw even better and faster than the world's best artist. But what I will draw won't stay permanent and what I draws may see me or not. What am I? -Riddles
Last Answer : A mirror. Humans can see it but objects cannot.
Description : An electric heater draws 5 kW of power for continuous hot water generation in an industry. How much quantity of water in litres per min can be heated from 30oC to 85oC ignoring losses?. a) 1.3 b) 78.18 c) 275 d) none of the above
Last Answer : a) 1.3
Description : A heating element of a hot plate on an electric cooking range draws 12 amperes from 240 V mains. How many kWh of energy will be consumed in one hour and 15 minutes
Last Answer : A heating element of a hot plate on an electric cooking range draws 12 amperes from 240 V mains. 3.2 kWh of energy will be consumed in one hour and 15 minutes.
Description : What effects on its surroundings do you expect from an object moving at relativistic speeds?
Last Answer : Grumpyfish is no physicist, but accelerating something only increases its effective mass, not its actual mass. So you shouldn’t see any increase in local gravity effects.
Description : Which of the following is not accomplished by agitation of liquids in agitators? (A) Dispersing gas in liquid (B) Blending of immiscible liquids (C) Dispersing immiscible liquid in form of emulsion (D) Suspending solid particles
Last Answer : (B) Blending of immiscible liquids
Description : In hydrometer analysis for a soil mass (A) Both meniscus correction and dispersing agent correction are additive (B) Both meniscus correction and dispersing agent correction are subtractive ... is subtractive (D) Meniscus correction is subtractive and dispersing agent correction is additive
Last Answer : (C) Meniscus correction is additive and dispersing agent correction is subtractive
Description : According to IS : 2720 - 1965, the composition of a dispersing solution used in pipette analysis for determining the size of particles, is (A) sodium-hexametaphosphate 33 g, sodium carbonate 7 g ... -hexametaphosphate 23 g, sodium carbonate 17 g and distilled water one litre (D) None of these
Last Answer : Answer: Option A
Description : Hydrometer readings are corrected for: (A) Temperature correction (B) Meniscus correction (C) Dispersing agent correction (D) Temperature, meniscus and dispersing agent corrections
Last Answer : Answer: Option D
Description : Large scale African slavery began as a means of: (a) Dispersing the captives of African warfare (b) Dispersing populations from overcrowded areas (c) Supplying labour for New World plantations (d) All of these (e) None of these
Last Answer : c) Supplying labour for New World plantations
Description : A fuse will blow for all the listed reasons EXCEPT ________. A. excessive vibration B. extremely hot surroundings C. loose fuse clips D. low contact resistance within the fuse
Last Answer : Answer: D
Description : The heated parts of an electrical machine dissipate heat into their surroundings by which of the following modes of heat dissipation ? (a) Conduction (b) Convection (c) Radiation (d) All ofthe above
Last Answer : (d) All ofthe above
Description : which object absorbs the most sound waves?
Last Answer : earplugs
Description : What does an object look like when it absorbs all the light ?
Last Answer : An object appears black when it absorbs all the light.
Description : An object which absorbs all colours and reflects none appears:
Last Answer : Black
Description : An object which absorbs all colours and reflects none appears: (1) White (2) Grey (3) Blue (4) Black
Last Answer : (4) Black Explanation: A surface that absorbs all colours, reflecting none, is said to be black. Black is not a colour; it absorbs all the colours of the visible spectrum and reflects none of them to the eyes. White is a colour.
Description : An object which absorbs all colours ap- pears as?
Description : An object which absorbs all colours and reflects none appears: (1) white (2) grey (3) blue (4) black
Last Answer : black
Description : What method of heat transfer to all objects give out heat their surroundings?
Last Answer : Need answer
Description : In adiabatic evaporative cooling, heat transfer between chamber and surroundings is ____ A. zero B. high C. low D. none of the mentioned
Last Answer : ANSWER : A
Description : Which law states, “The rate of loss of heat by a body is directly proportional to the difference in temperature between the body and the surroundings.” (1) Doppler’s Effect (2) Newton’s law of cooling (3) Kirchhoff’s Law (4) Stefan’s Law
Last Answer : (2) Newton’s law of cooling Explanation: Kirchhoff’s Law – Kirchhoff’s Law signifies that good absorbers are good emitters. Stefan’s Law – The radiant energy emitted by a black body per unit area per unit time is directly proportional to the fourth power of its absolute temperature.
Description : Which law states, "The rate of loss of heat by a body is directly proportional to the difference in temperature between the body and the surroundings." (1) Doppler's Effect (2) Newton's law of cooling (3) Kirchhoff's Law (4) Stefan's Law
Last Answer : (2) Newton's law of cooling Explanation: Kirchhoff's Law - Kirchhoff's Law signifies that good absorbers are good emitters. Stefan's Law - The radiant energy emitted by a black body per unit area per unit time is directly proportional to the fourth power of its absolute temperature.
Description : When temperature difference between liquid and its surroundings is doubled, the rate of loss of heat will: (1) remain same (2) double (3) three times (4) four times
Last Answer : (2) double Explanation: According to Newton's law of cooling, the rate of loss of heat of a body is directly proportional to the difference between the temperature of hot body and temperature of the surroundings, provided that the difference in temperature is small enough.
Description : Which law states, "The rate of loss of heat by a body is directly proportional to the difference in temperature between the body and the surroundings"? (1) Doppler's Effect (2) Newton's law of cooling (3) Kirchhoff's Law (4) Stefan's Law
Last Answer : (2) Newton's law of cooling Explanation: Newton's Law of Cooling states that the rate of change of the temperature of an object is proportional to the difference between its own temperature and the ambient temperature.
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 : In a cooling tower, water becomes cool by (A) Loosing sensible heat (B) Heat transfer to surroundings (C) Vaporisation due to heat loss to air (D) Loosing latent heat
Last Answer : (A) Loosing sensible heat
Description : In a/an __________ reactor, there is exchange of heat with the surroundings with sizeable temperature variation. (A) Adiabatic (B) Isothermal (C) Non-adiabatic (D) None of these
Last Answer : (C) Non-adiabatic
Description : Pick out the correct statement: (A) In an isothermal system, irreversible work is more than reversible work (B) Under reversible conditions, the adiabatic work is less than isothermal work (C) ... state functions' (D) Matter and energy cannot be exchanged with the surroundings in a closed system
Last Answer : (B) Under reversible conditions, the adiabatic work is less than isothermal work
Description : Work required for compression of a gas contained in a cylinder is 7000 kJ. During compression, heat interaction of 3000 kJ causes the surroundings to be heated. Internal energy change of the gas during the compression is __________ kJ. (A) +4000 (B) -4000 (C) 10000 (D) -10000
Last Answer : (A) +4000
Description : For a body cooling in a draft, the rate of heat loss is proportional to the difference in temperature between the body and its surroundings. a. Nemst Effect b. Caloric Theory c. Joule’s Law d. Newton’s Law of Cooling
Last Answer : Newton’s Law of Cooling
Description : What is the thermodynamic STATE function that is directly associated with a constant pressure process in which heat is exchanged between system and surroundings?
Last Answer : ANSWER: DELTA H
Last Answer : double
Description : The temperature of water at the bottom of a large waterfall is higher than that of the water at the top, because - (1) the falling water absorbs heat from the Sun. (2) the water at the bottom has ... of the falling water is converted into heat. (4) rocks on the bed of the river give out heat.
Last Answer : (3) the kinetic energy of the falling water is converted into heat. Explanation: The water gains kinetic energy as it falls down and loses its potential energy. Assuming no other losses, part of the kinetic energy gain of water is converted into heat, raising the temperature of water.
Description : The temperature of water at the bottom of a large waterfall is higher than that of the water at the top. because (1) the falling water absorbs heat from the Sun. (2) the water at the bottom has greater ... of the falling water is converted into heat. (4) rocks on the bed of the river give out heat.
Last Answer : the kinetic energy of the falling water is converted into heat.
Description : According to Kelvin-Planck's statement of second law of thermodynamics, A. it is impossible to construct an engine working on a cyclic process, whose sole purpose is to convert heat energy into work B. it ... other than the transfer of heat from a cold body to a hot body D. none of the above
Last Answer : Answer: A
Description : A black surface absorbs more heat radiations as compared to a white or a reflecting surface under identical conditions. List two solar devices which make use of this property in their design. -Science
Last Answer : Solar cooker, solar water heater.
Description : If a gas absorbs `200J` of heat and expands by `500 cm^(3)` against a constant pressure of `2 xx 10^(5) N m^(-2)`, then the change in internal energy
Last Answer : If a gas absorbs `200J` of heat and expands by `500 cm^(3)` against a constant pressure of `2 xx 10^(5) N ... . `-100 J` C. `+100 J` D. None of these
Description : A system absorbs reversibly 600 J of heat and performs 250 J of work. The increase in the internal energy of system is :-
Last Answer : A system absorbs reversibly 600 J of heat and performs 250 J of work. The increase in the internal energy of system ... J B. 250 J C. 600 J D. 350 J
Description : What type of surfaces absorbs heat?
Last Answer : Dark, rough, and/or porous surfaces absorb the most heat (ex.Asphalt)
Description : What is the best term to describe a chemical reaction that absorbs heat energy?
Last Answer : What is the answer ?
Description : When air passes through silica gel, A. it absorbs water vapour molecules B. latent heat of condensation is released C.dbt of air increases D. all of the mentioned
Last Answer : ANSWER : D
Description : An iron hammer, lying in the sun, appears much hotter than its wooden handle because (a) iron is at a higher temperature (b) iron is darker than wood (c) iron absorbs more heat (d) iron is a good conductor of heat
Last Answer : Ans:(d)
Description : The water from a hand pump is warm in winter because - (1) our body is cold in winter and the water appears to be warm (2) the temperature inside the Earth is higher than the atmospheric ... causes friction which warms up the water (4) inside water comes out and absorbs heat from the environment
Last Answer : (2) the temperature inside the Earth is higher than the atmospheric temperature
Description : Wollen clothes keep the body warm because – (1) Wool increases the temperature of the body (2) Wool is a had conductor (3) Wool absorbs radiant heat from outer objects (4) Wool rejects heat from the outer objects
Last Answer : (2) Wool is a had conductor Explanation: It is just because woolen clothes have fibres and between those fibres air is trapped which reduces heat loss. Air reduces heat loss because it is an ... have a greater bulk than other textiles, and retain air, which causes the product to retain heat.
Description : The water from a hand pump is warm in winter because - (1) Our body is cold in winter and the water appears to be warm (2) The temperature inside the earth is higher than the atmospheric ... causes friction which warms up the water (4) Inside water comes out and absorbs heat from the environment
Last Answer : (2) The temperature inside the earth is higher than the atmospheric temperature Explanation: In winter, the outside temperature is lower than that of water flowing out of the pump, and therefore, the ... the outside temperature is higher than the water of the pump, and therefore, it feels cold.