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Person's Oxygen Requirements

In one hour the average person at rest consumes 14.5 L of oxygen at a pressure of 1 atm. and a temperature of 20 degree C. A person at rest inhales and exhales 0.5 L of air with each breath. The inhaled air is 21.0 % oxygen, and the exhaled air is 16.3 % oxygen. a) How many breaths per minute will satisfy the person's oxygen

Expansion Coefficient for Aluminum Rivets in Airplane Construction

Ensuring a tight fit - aluminum rivets used in airplane construction are made slightly larger than the rivet holes and cooled by "dry ice" (solid CO2) before being driven. If the diameter of a hole is 4.500mm, what should be the diameter of a rivet at 23.0 C if its diameter is equal to that of the hole when the rivet is cooled t

The Temperature Gradient from Inside to Outside the Wall

A wall has an inside temperature 149 Celsius and outside temperature 22 Celsius. Its area is 6 m^2 and its uniform thickness is .38m. What is the temperature gradient from inside to outside? If the inside temperature decreased, thereby increasing the temperature difference by a factor of 1.749 what would be the temperature gradi

Saturation Temperature

How do you determine when the saturation temperature is reached when dissolving at various temperatures?

Quadratics and optimal temperature

An amateur brewer has made some experimental batches of beer with the aim of optimizing the taste of future batches. The brewer rates the beer on a scale of 0-10. Except for the brewing temperature, the brewer has already settled on the other aspects of the brewing process. These latest batches are meant to assist in the determi

Combined Gas Laws: Pressure, Volume and Temperature

P6. Solve problems involving the gas laws... Task 1: The temperature of 2 liters of gas at 100 kPa rises from 18°C to 163.5°C. If the volume remains constant, what does the pressure change to? Task 2: In an air pump, the cylinder volume is 20 liters when the piston is at the top of its compression stroke. The pressure is the

Pressure, Volume and Temperature

Fill an empty 2 liter bottle 1/3 full with the hottest tap water you can get. Immediately screw the cap on. Set the bottle aside and let it cool. The side buckles. Why?

Physics: Problems Based on Refrigeration

Hi, I need some assistance solving the following problems: 1. An ice chest is maintained at 0 degrees Celsius by ice placed in it. The chest is cubical with each inside wall having an area of 1200cm^2 and a thickness of 4cm. Each wall is made of foam plastic with k= 1.3X10^-4 cal/cm/s/C. How much ice will melt in the chest i

Expansion Of Steel Rods During Temperature Change

A steel meter rod reads the correct length of objects at 20 degrees C. If the temperature of the steel rod increases to 30 degrees C and the scale to measure the length of an object, it will a) Give the correct length of the object b) Underestimate the actual length of an object c) Overestimate the actual length of the obje

A temperature

A temperature of -162 degrees C corresponds to a. 111k b. -111k c. -162k d. 162k

Volume; Density; Mass; Temperature - Frictional Heat

1. What volume of foam (lifevest) with a given density will be needed to keep a person, with a given mass and density, 1/3 out of the water? 2. A 20g lead bullet moving at 400m/s strikes a tree. How much will the temperature be raised if 1/2 of the frictional heat goes into the bullet?

Work done on gas, entropy changes, temperature.

1. A 4 L sample of a diatomic gas with specific heat ratio 1.4, confined to a cylinder, is carried through a closed cycle. The gas is initially at 1 atm and 300 K. First, its pressure is tripled under constant volume. Then, it expands adiabatically to its original pressure. Finally, the gas is compressed isobarically to its

Solving for Temperature

Question: Both the pressure and volume of a given sample of an ideal gas double. This means that its temperature in kelvins must. a. Quadruple b. Reduce to one fourth its original value c. Reduce to one half its original value d. Remain unchanged. e. Double

Consider a flat steel plate

Consider a flat steel plate with a hole through its center. when the plates temperature is decreased, the whole will a. expand b. expand if it takes up less than half the plates surface area c. contract only if it takes up more than half the plates surface area d. contract

Matrix inversion; temperature node distribution

Please show all the work. The matrix inversion method has to be shown in detail, the formula used in the class for temperature node distribution was Tm+1,n + Tm-1, n + Tm, n+1 + Tm, n-1 ? 4Tm,n =0 (where ?m? is the X?axis and ?n? is the Y-axis) Please see attachment for problem. Thanks.

Manufacturing Processes

1. Explain why studying the types of chips produced is important in understanding cutting operations. 2. Tool life can be almost infinite at low cutting speeds. Would you recommend that all machining be done at low speeds? Explain. 3. Explain the consequences of allowing temperatures to rise to high levels in cutting? 4. What

Stoichiometric Combustion and Typical Jet Turbine Combustion

Determine, using the chemical balance equations, the stoichiometric fuel:air ratio for the complete combustion of C12H26 in air of 21% Oxygen, 78% nitrogen. Using this value of AFR, determine the combustion temperature rise for a typical gas turbine (T2 = 250C). Note the two charts provide different ranges on the vertical and

Increasing the Temperature of a Gas

Please provide some assistance solving this problem. Question: If a house has insulated walls, and it contains a volume of 100 m^3 of air at 300 K, what is the energy required to increase the temperature of this diatomic gas by 2 degrees Celsius?


At what temperature is the Fahrenheit value equal to the temperature in Kelvins?

Tire pressure and temperature

The pressure of an automobile tire is measured to be 200 kPa (gage) before a trip and 220 kPa (gage) after the trip at a location where the atmospheric pressure is 90 kPa. If the temperature of air in the tire before the trip is 25 °C, the air temperature after the trip is?

Vapour Pressure and mass of water vapor

A room is filled with saturated moist air at 30oC and a total pressure of 100 kPa. If the mass of dry air in the room is 100 kg, the mass of water vapor is:

Temperature of an Expanded Gas

If 2.0 liters of a gas origninally at 2.0 atm and 300 K is expanded to 5.0 liters at 1.0 atm what is its new temperature?

Solving for Pressure

Question: An automobile tire is pumped up to an absolute pressure of 33 lb/in^2, with air at a temperature of 40.0 degrees Fahrenheit. After driving for several hours, the temperature in the tire reaches 120 degrees Fahrenheit. Find the pressure in the tire at that point in SI units.

Volume of a balloon

A large, aluminumized-Mylar balloon contains 1.000 m^3 of helium when filled outdoors at 0 degrees C on a winter's day. What will its volume be at home at 20 dgrees C?

Calculating volume

A chamber sealed with a moveable piston contains 5.50 litres of hydrogen at 28 degrees C and 81.3 kPa. What would its new volume be at STP?


A 1.00-m^3 tank is filled with nitrogen gas to a gauge pressure of 20.0 atm. It is then connected through a valve to 9.00-m^3 evacuated chamber. The valve is opened just a little, and the gas slowly flows unitl it finally stops on its own. Given that the temperature was constant throughout the transfer, what is the pressure i