How does a warm rock transfer thermal energy to your hand?

1 Answer

Answer :

If you do not touch it, by radiation. If you touch it then by radiation and conduction.

Related questions

Description : When a warm object is heated up why does the thermal radiation emits change?

Last Answer : Feel Free to Answer

Description : When a warm object is heated up why does the thermal radiation it emits changes?

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Description : A girl throws a 2 kilogram rock vertically upward. It reaches a maximum height of 5 meters. What is the kinetic energy of the rock the instant it leaves the girl's hand?

Last Answer : ANSWER: 100 JOULES (accept 98 joules)

Description : Do hand warmers really keep your hands warm in the winter months?

Last Answer : Hand warmers definitely work in keeping your hands warm in cold winter months. There are many different kinds of hand warmers, so it is important to know exactly what you are looking for when you purchase ... problem for you, you can wait until the product has cooled for a few minutes before using.

Description : The water from a hand pump is warm in winter because

Last Answer : The temperature inside the earth is higher than the atmospheric temperature 517.

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 : 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 : 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.

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.

Description : Why is water from a hand pump warm in winter and cold in summer?

Last Answer : Answer: In winter, the outside temperature is lower than that of water flowing out of the pump, and therefore, the water is warm. Whereas in summer, the outside temperature is higher than the water of the pump, and therefore, it feels cold.

Description : Pick up the incorrect statement applicable to the field test of good cement. (A) When one thrusts one's hand into a bag of cement, one should feel warm (B) The colour of the cement is bluish (C) By rubbing cement in between fingers, one should feed rough (D) All the above

Last Answer : Answer: Option 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 : The temperature inside the earth is higher than the atmospheric temperature

Description : How insulation between the outer and inner walls of a home hleps to reduce thermal energy transfer?

Last Answer : Need answer

Description : What is the word Transfer of thermal energy when particles in a heated fluid rise?

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Description : How is the transfer of thermal energy from electric devices regulated?

Last Answer : A device that converts electric energy into thermal energy. A device that regulates the temperature of a system. A device that uses electric energy to transfer thermal energy from a cooler location to a warmer location. A machine that converts thermal energy into mechanical energy.

Description : Which term defines something that does not transfer thermal energy efficiently?

Last Answer : conductor

Description : Molecular diffusion is caused by the (A) Transfer of molecules from low concentration to high concentration region (B) Thermal energy of the molecules (C) Activation energy of the molecules (D) Potential energy of the molecules

Last Answer : (B) Thermal energy of the molecules

Description : Which of the following best describes heat?  a. The capacity to do work  b. Forces times distances  c. Sum of thermal and chemical energy  d. An energy transfer due to temperature difference

Last Answer : An energy transfer due to temperature difference

Description : What are the only two forms of energy interactions associated with a closed system?  A. Kinetic energy and heat  B. Heat transfer and work  C. Thermal energy and chemical energy  D. Latent energy and thermal energy

Last Answer : Heat transfer and work

Description : Which of the following represents the perpetual motion of the first kind  (a) engine with 100% thermal efficiency  (b) a fully reversible engine  (c) transfer of heat energy from low ... its own energy  (e) production of energy by temperature differential in sea water at different levels.

Last Answer : Answer : d

Description : When warm and cold liquids are mixed, the heat transfer is mainly by (A) Conduction (B) Convection (C) Radiation (D) Both (A) & (C

Last Answer : (B) Convection

Description : The finite element methods can be applied in ---------areas. a.thermal b.soil and rock mechanics c.vibration d.all of the above

Last Answer : d.all of the above

Description : (3) reflection of light due to the presence of free electrons Explanation: Lustre (or luster) is the way light interacts with the surface of a crystal, rock, or mineral. The word ... conductivity, and high density. Typically they are malleable and ductile, deforming -under stress without cleaving.

Last Answer : Cloud is a colloidal dispersion of – (1) Air in a dispersion medium of water (2) Fog in a dispersion medium of water (3) Mist in a dispersion medium of air (4) Water drops in a dispersion medium of air

Description : The illustrated motor fails to start and gives a loud hum when the start button is depressed, your first action should be to __________. EL-0007 A. disassemble the motor to fix the centrifical ... D. hold the 'M' contactor closed by hand while wearing electrical safety gloves to get motor started

Last Answer : Answer: B

Description : Which of the following are methods of heat transfer? (1) Convection (2) Evaporation (3) Revolution (4) Thermal Expansion

Last Answer : (1) Convection Explanation: Convection is the transfer of heat from one place to another by the movement of fluids. It is usually the dominant form of heat transfer (convection) in liquids and ... the combined processes of conduction (heat diffusion) and advection (heat transfer by bulk fluid flow).

Description : Which of the following type of printer uses a thermal transfer ribbon that contains wax-based ink? A. Direct Thermal B. Thermal Wax transfer C. Both (A) and (B) D. None of the Above

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Description : Thermal transfer printer can be divided into ______ types. A. Three B. Four C. Six D. Two

Last Answer : D. Two Direct Thermal Printer, Thermal Wax transfer Printer

Description : A thermal transfer printer is a ________ printer that uses heat to register an impression on paper. A. Impact B. Non-impact C. Both (A) and (B) D. None of the Above

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Description : . (NSh /NRe .NSc ) is termed in mass transfer operation as the (A) Stanton number (B) Peclet number (C) Thermal diffusivity (D) Momentum diffusivity

Last Answer : (A) Stanton number

Description : Diffusion co-efficient generally depends upon the temperature, pressure & the nature of the components of the system. Its dimension is not the same as that of the (A) Mass transfer co-efficient (B) Thermal diffusivity (C) Kinematic viscosity (D) Volumetric diffusivity

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Description : Lewis number, which is important in problems involving simultaneous heat and mass transfer, is the ratio of (A) Mass diffusivity to momentum diffusivity (B) Thermal diffusivity to mass diffusivity (C) Momentum diffusivity to thermal diffusivity (D) None of these

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Description : Heat transfer by natural convection is enhanced in system with (A) High viscosity (B) High co-efficient of thermal expansio

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Description : In a heat exchanger, floating head is provided to (A) Facilitate cleaning of the exchanger (B) Increase the heat transfer area (C) Relieve stresses caused by thermal expansion (D) Increase log mean temperature gradient

Last Answer : (C) Relieve stresses caused by thermal expansion

Description : Overall thermal resistance for conductive heat transfer through a series of flat resistances is equal to the (A) Maximum resistance in the series (B) Sum of all resistances (C) Average of all resistances (D) Minimum resistance presents in the series

Last Answer : (B) Sum of all resistances

Description : Thermal diffusivity is the most important in heat transfer by (A) Conduction (B) Radiation

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Description : Heat transfer occurs by natural convection because change in temperature causes difference in (A) Viscosity (B) Density (C) Thermal conductivity (D) Heat capacity

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Description : A metal wire of 0.01 m dia and thermal conductivity 200 W/m.K is exposed to a fluid stream with a convective heat transfer coefficient of 100 W/m2 .K. The Biot number is (A) 5.6 (B) 0.025 (C) 3.5 (D) 0.0035

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Description : The critical radius of insulation for a spherical shell is (where, K = thermal conductivity of insulating material h0 = heat transfer coefficient at the outer surface) (A) K/h0 (B) 2K/h0 (C) h0 /K (D) h0 /2K

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Description : Analogy between mass and heat transfer is not applicable in case of (A) Same velocity profile or equal eddy diffusivities (B) Thermal or pressure mass diffusion (C) Viscous heating or chemical reaction (D) Both (B) and (C)

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Description : Heat transfer rate per unit area is called (A) Thermal conductivity (B) Heat flux (C) Heat transfer co-efficient (D) Thermal diffusivity

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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 : . 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

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Description : Heat transfer rate described by Fourier's law will decrease, if the __________ increases. (A) Thermal conductivity (B) Thickness (C) Temperature difference (D) Heat transfer area

Last Answer : (B) Thickness

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Description : In Fourier's law, the proportionality constant is called the (A) Heat transfer co-efficient (B) Thermal diffusivity (C) Thermal conductivity (D) Stefan-Boltzmann constant

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Description : Fluid motion in the natural convection heat transfer between a solid surface and a fluid in contact with it, results from the (A) Existence of thermal boundary layer (B) Temperature gradient produced ... difference (C) Buoyancy of the bubbles produced at active nucleation site (D) None of these

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Description : Pick out the correct statement. (A) 1 kcal/hr.m.°C is equal to 1 BTU/hr. ft.°F (B) In steady state heat conduction, the only property of the substance which determines the ... in the direction of temperature rise (D) In heat transfer by forced convection, Grashoff number is very important

Last Answer : (B) In steady state heat conduction, the only property of the substance which determines the temperature distribution, is the thermal conductivity

Description : Walls of a cubical oven are of thickness l, and they are made of material of thermal conductivity k. The temperature inside the oven is 100°C and the inside heat transfer co-efficient is 3k/l'. If the wall temperature ... wall temperature in degree centigrade? (A) 35.5 (B) 43.75 (C) 81.25 (D) 48.25

Last Answer : (C) 81.25

Description : Nusselt number/Biot number varies (A) Inversely with thermal conductivity (B) Directly with heat transfer co-efficient (C) Directly with thermal conductivity (D) Inversely with the dimension of the solid

Last Answer : (A) Inversely with thermal conductivity

Description : A steam pipe is intended to be insulated with two layers of insulating materials of different thermal conductivities. For minimum heat transfer to take place (A) The better insulation material should be put just ... to which insulating material is to be put inside (i.e., just next to the pipe)

Last Answer : (A) The better insulation material should be put just next to pipe (i.e., inside)