conductivity two times that of cork. Assume there are no windows or doors. The walls' surface area is 1350000 cm? and their inside surface is at 19°C, while their outside surface is at 5°C. (Thermal conductivity of cork is 0.042 W/m°C) (i) Calculate the rate of heat conduction through house walls in watt? (4 marks) (ii) How many 400W room heaters would be needed to balance the heat transfer due to conduction?(approximate number) (1 mark)

conductivity two times that of cork. Assume there are no windows or doors. The walls' surface area is 1350000 cm? and their inside surface is at 19°C, while their outside surface is at 5°C. (Thermal conductivity of cork is 0.042 W/m°C) (i) Calculate the rate of heat conduction through house walls in watt? (4 marks) (ii) How many 400W room heaters would be needed to balance the heat transfer due to conduction?(approximate number) (1 mark)

College Physics

11th Edition

ISBN:9781305952300

Author:Raymond A. Serway, Chris Vuille

Publisher:Raymond A. Serway, Chris Vuille

Chapter1: Units, Trigonometry. And Vectors

Section: Chapter Questions

Problem 1CQ: Estimate the order of magnitude of the length, in meters, of each of the following; (a) a mouse, (b)...

See similar textbooks

Similar questions

An automobile has a mass of 1,547 kg, and its aluminum brakes have an overall mass of 10.2 kg. (a) Assuming all the internal energy transformed by friction when the car stops is deposited in the brakes and neglecting energy transfer, how many times could the car be braked to rest starting from 29.0 m/s before the brakes would begin to melt? (Assume an initial temperature of 20.0°C. Count only the number of times the car can come to a complete stop without the brakes melting in the process. The melting point of aluminum is 660°C.)
1. (a) The number of kilocalories in food is determined by calorimetry techniques in which the food is burned and the amount of heat transfer is measured. How many kilocalories per gram are there in a 6-g peanut if the energy from burning it is transferred to 0.5 kg of water held in a 0.1 -kg aluminum cup, causing a 55.9 °C temperature increase? The specific heat of water is 1.00 kcal/kg °C, and the specific heat of aluminum cup is 0.215 kcal/kg °C. Q kcal/g mp (b) Compare your answer to labeling information found on a package of peanuts and comment on whether the values are consistent. A label for unsalted dry roasted peanuts says that 30 g contains 185 calories (kcal). Find the (Q/m) from calorimetry techniques of the label on a box of roasted peanuts. Q EGE 4.86 m cal m label
The number of kilocalories in food is determined by calorimetry techniques in which the food is burned and the amount of heat transfer is measured. How many kilocalories per gram are there in a 5.00-g peanut if the energy from burning it is transferred to 0.500 kg of water held in a 0.100-kg aluminum cup, causing a 54.9°C temperature increase?
1) The walls of a house are 11 cm thick and have an average thermal conductivity two times that of cork. The walls' surface area is 850000 cm2 and their inside surface is at 18°C, while their outside surface is at 4°C. (Thermal conductivity of cork is 0.036 W/m°C). Calculate, (i) The rate of heat conduction through house walls in Watts: (1) Amount of heat conducted in Joules, in 5 min: 2) A spherical infrared heater of radius 6.5 cm and an emissivity of 0.82 radiates 0.48 kW of power. Given, Stefan's constant = 5.67x10 Wm K Calculate, Temperature of the heater in Celsius: 1) A 275-turns square loop of 34 cm on a side, carrying a current of 22 A creates a torque of 385 N m when the plane of the coil makes an angle 38° with the magnetic field.
(a) Calculate the rate of heat conduction (in W) through house walls that are 11.5 cm thick and that have an average thermal conductivity twice that of glass wool. Assume there are no windows or doors. The surface area of the walls is 150 m2 and their inside surface is at 20.0°C, while their outside surface is at 5.00°C. 1565.21 (b) How many 1 kW room heaters would be needed to balance the heat transfer due to conduction? (Round your answer to the next whole integer.) 2 1 kW room heaters
Radioactive decay of elements in the earth’s interior results in a mean heat flux through the Earth’s surfaceof 5×10−2Wm−2. What is the flux expressed as a fraction of the energy flux due to thermal re-radiation of absorbed solar energy? If radioactive decay were the only heat source for the Earth, what would the Earth’s temperature be?
A small electric immersion heater is used to heat 79 g of water for a cup of instant coffee. The heater is labeled “72 watts" (it converts electrical energy to thermal energy at this rate). Calculate the time required to bring all this water from 20°C to 100°C, ignoring any heat losses. (The specific heat of water is 4186 J/kg-K.) Number Units
(a) Calculate the rate of heat conduction through house walls that are 13.0 cm thick and that have an average thermal conductivity twice that of glass wool. Assume there are no windows or doors. The surface area of the walls is 120m^2 and their inside surface is at 18.0ºC, while their outside surface is at 5.00ºC. (b) How many 1-kW room heaters would be needed to balance the heat transfer due to conduction?
Suppose a human body's core internal temperature is 37.0°C, the skin temperature is 34.0°C, the thickness of the tissues between averages 0.95 cm, and the surface area is 1.435 m2. -Calculate the rate of heat conduction, in watts, out of the human body.
A glass windowpane in a home is 0.62 cm thick and has dimensions of 1.4 m x 2.3m. On a certain day, the indoor temperature is 21°C and the outdoor temperature is 0ºC. (a) What is the rate at which energy is transferred by heat through the glass? (b) How much energy is lost through the window in one day, assuming the temperatures inside and outside remain constant? Need Help? Readi Submit Answer