Physics Conduction: Hours required for $1 worth of energy conducted through a wall

In an electrically heated home, the temperature of the ground in contact with a concrete basement wall is 12.8 degrees Celsius. The temperature at the inside surface of the wall is 20.0 degrees Celsius. The wall is 0.10m thick and has an area of 9.0m^2. Assume one kilowatt hour of electrical energy costs $0.10. How many hour ...continues

Physics Conduction: Calculate the ratio of heat loss between wool and goose down

A skier wears a jacket filled with goose down that is 15mm thick. Another skier wears a wool sweater that is 5.0mm thick. Both have the same surface area. Assuming the temperature difference between the inner and outer surfaces of each garment is the same, calculate the ratio (wool/goose down) of the heat lost due to conducti ...continues

Physics: Linear thermal expansion of aircraft carrier in the Mediterranean Sea.

A steel aircraft carrier is 370m long when moving through the icy North Atlantic at a temperature of 2.0 degrees Celsius. By how much does the carrier lengthen when it is traveling in the warm Mediterranean Sea at a temperature of 21 degrees Celsius?

Physics: Mass and heat to calculate a final temperature of liquid water from ice

A 10.0 kg block of ice has a temperature of -10.0 degrees Celsius. The pressure is one atmosphere. The block absorbs 4.11 * 10^6 J of heat. What is the final temperature of the liquid water?

Physics: Calculate molecular mass and moles of a chlorophyll-a molecule.

The chlorophyll-a molecule, C55H72MgN4O5, is important in photosynthesis. (a) Determine its molecular mass (in atomic mass units). (b) What is the mass (in grams) of 3.00 moles of chlorophyll-a molecules?

Physics ideal gas law: Find air temperature inside the tires at end of a trip

At the start of a trip, a driver adjusts the absolute pressure in her tires to be 2.81 * 10^5 Pa when the outdoor temperature is 284K. At the end of the trip she measures the pressure to be 3.01 * 10^5 Pa. Ignoring the expansion of the tires, find the air temperature inside the tires at the end of the trip.

Physics: Pressure, height, and Kelvins in a gas-filled cylinder.

A frictionless gas-filled cylinder is fitted with a movable piston. The block resting on the top of the piston determines the constant pressure that the gas has. The height h is 0.120 m when the temperature is 273K and increases as the temperature increases. What is the value of h when the temperature reaches 318K?

Thermodynamics: Calculate change in internal energy of a system, the environment.

A system does 164 J of work on its environment and gains 77 J of heat in the process. Find the change in the internal energy of (a) the system (b) the environment

Physics: Venturi meter readings sphere density.

1a) A venturi meter has 0.02556m^3 of flow per second through its 45mm dia throat.If the pipe is 58mm in diameter,what will the differential reading of mercury across it be? b)A metal sphere 60mm in dia is submerged in oil with a relative density of 0.9.Need to find the density of the sphere.There is a downward force of 8.31N wh ...continues

Periodic Waves: Calculate time given speed of a transverse wave, amplitude, distance.

The speed of a transverse wave on a string is 450 m/s, while the wavelength is 0.18m. The amplitude of the wave is 2.0mm. How much time is required for a particle of the string to move through a total distance of 1.0 km?