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Lenght and Frequency of a String

One type of steel has a density of 8000 kg/m^3 and a breaking stress of 7.1×108 N/m^2. A cylindrical guitar string is to be made out of a quantity of steel with a mass of 4.50 g. a). What is the length of the longest and thinnest string that can be placed under a tension of 890 N without breaking? b). What is the highest

Using Different Thermometers for Accuracy

Describe the thermometer you would use for measuring the temperature of each of the objects listed below, indicating the thermometers' approximate accuracy: a) A domestic oven; b) A sick child; c) A cryostat at about 4K; d) The sun.

A carbon wire and a nichrome wire

A carbon wire and a nichrome wire are connected one after the other. If the combination has total resistance of 11.0 k ohms at 20° C, what is the resistance of each wire at 20° C so that the resistance of the combination does not change with temperature? It seems as though resistivity may need to be considered in order fo

Food processing techniques.

What are the differences between (a) Pasteurization, (b) Commercial sterilization, and (c) Ultrahigh temperature processing (UHT). The discussion should be based on the processing method involved and preservation principles behind each method. In addition, what will be the shelf-life expectancy for food products treated by each

The average thermal conductivity of the walls and roof of a house

1)The average thermal conductivity of the walls and roof of a house is 4.8 x 10"4 kW m"1°C~1 and their average thickness is 21.0 cm. The house is heated with natural gas,with a heat of combustion (energy released per cubic metre of gas burned) of 9300 kcal.m"3. How many cubic metres of gas must be burned each day to maintain a

Adiabatic processes temperature profile.

Please assist in understanding these problems: 1a) If the temperature on the surface over land is 310 K, and the temperature at 0.5 km is 305 K, what is the ambient atmospheric lapse rate? If a parcel of air starts to rise at the dry adiabatic lapse rate, what would be the temperature of the parcel at 0.5 km? Is this ambient

Modeling a situation

Your company was very impressed with your results from the recent study. They have asked that you investigate another location for them and present this new promising location at the upcoming sales meeting. Again, it is your job to check out the various areas and the friendliness for business. One of the factors of interest is t

Tension in a pipe due to change in temperature.

When the hot water in a certain upstairs bathroom is turned on, a series of 18 "ticks" is heard as the copper hot-water pipe slowly heats up and increases in length. The pipe runs vertically from the hot-water heater in the basement, through a hole in the floor 5.0 m above the water heater. The "tick" are caused by the pipe stic

Determining depth of a lake

At a height of 5 meters above the surface of a freshwater lake, a sound pulse is generated. The echo from the bottom of the lake returns to the point of origin 0.140 s later. The air and water temperatures are 20°C. How deep is the lake?

Ideal gas law problems

A.) At the start of a trip, a driver adjusts the absolute pressure in her tires to be 2.79 105 Pa when the outdoor temperature is 284 K. At the end of the trip she measures the pressure to be 3.02 105 Pa. Ignoring the expansion of the tires, find the air temperature inside the tires at the end of the trip. B.) Oxygen for h

Temperature Change

When we add 50.0 mL of 0.250 M HCl to 50.0 mL of 0.250 M NaOH, the temperature increases by 1.71 degrees C and 715 J of heat is evolved by the reaction. Which of the following will be true when we add 100.0 mL of 0.125 M HCl to 100.0 mL of 0.125 M NaOH? A. The temperature change will be 1.71 C and the heat evolved will be 71

Resistance: Platinum Thermometer

The resistance of a platinum resistance thermometer is 125 ohms when its temperature is 20.0 degrees Celsius. The wire is then immersed in boiling chlorine, and the resistance drops to 99.6 ohms. The temperature coefficient of resistivity of platinum is 3.72 x 10^-3 (Celsius^-1). What is the temperature of the boiling chlorine?


1. For the reaction N2 + O2 → 2NO, Kc = 4.08 x 10-4 at 2000K. What is Kc at this same temperature for the reaction, NO → 1/2 O2 + 1/2 N2 2. What is the total pressure of the gases above the carbon for the reaction C + CO2 → 2CO when the pressure of CO is ten times the pressure of CO2? The equilibrium c

Energy states and rotational states for molecules at room temperature

3. Probable energy states for molecules at room temperature (a) Suppose we have an system that has the following allowed electronic energy states: 0.2 eV, 2.0 eV, 3.0 eV, 10eV. What is the probability of the system to be at each of these energy states at 350K, 1000K? (b) Suppose we have a system that has the following allo


Problem: Which would require more heat, melting 500 g of 00C ice or turning 500 g of 1000C water into steam? Problem: A 500g sample of an unknown material requires 750 calories of heat to raise its temperature by 500C. Use equation to solve the problem.

Financial or Public Economic Questions

1. Consider an economy with two people, Henry and Catherine, who consume two commodities, bread and water. Suppose that, due to a drought, the authorities decide to allocate exactly half the available water to each person. In order to prevent one person from "exploiting" the other, neither person may trade away any water to t

Speed of Sound in a Gas

A monatomic ideal gas(y=1.67) is contained within a box whose volume is 2.5 m^3. The pressure of the gas is 3.5 x 10^5 Pa. The total mass of the gas is 2.3 kg. What is the speed of sound in the gas?

Sound Travel Distance; wavelengths in the distance traveled

The distance between a loudspeaker and the left ear of a listener is 2.70 m. a.) How long would it take for sound to travel this distance if the air temperature is 20 degrees C. b.) Assuming that the sound frequency is 523 Hz, how many wavelengths of sound are contained in this distance?

Length of Wire To Support a Mass

I have rubber as having a negative coefficient of thermal expansion when it is under tension and that value being -43 x 10^-6/deg K. A rubberband will shrink when heated if it is under tension. The problem has a large rubberband attached to a ceiling, a wire of aluminum of unknown cm. length attached to the hanging end of t