You close off the nozzle of a bicycle tire pump and very lowly depress the plunger so
Question:
(a) Is the work done by the air in the pump positive or negative?
(b) Is the heat flow to the air positive or negative?
(c) What can you say about the relative magnitudes of the eat flow and the work? Explain.
Step by Step Answer:
IDENTIFY Apply AUQW SET UP For an ideal gas U depends only on T EXECUTE a V decrease...View the full answer
Related Video
An air pump is a device used to inflate or deflate objects by moving air in or out of them. There are many different types of air pumps, ranging from manual hand pumps to electrically powered pumps, and they are used for a variety of purposes. John had trouble blowing up many balloons without a balloon pump and experienced pain. He solved this problem by using an empty plastic bottle with a rectangular-shaped hole in the cap, a cut piece of balloon stretched over it, and a small hole in the bottle. By pressing and releasing the bottle, he created an air pump to inflate the balloons without any discomfort. Air pumps utilize fluid mechanics and thermodynamics principles to increase air pressure inside an object being inflated, such as a bicycle tire. The ideal gas law is used to calculate the pressure inside the tire. As air pressure increases, the object becomes more rigid and can support more weight. The efficiency of the pump is determined by how much of the work done is converted into useful work, such as inflating the tire, and how much is lost as heat. Understanding these principles is important to effectively use and optimize the use of air pumps.
Students also viewed these Thermodynamics questions
-
If A2 = A, what can you say about det A?
-
Is the expression only valid for an ideal gas if V is constant? T, AUr = [ CydT = n[ Cy,maT
-
Propane gas (C3H8) behaves like an ideal gas with y = 1.127. Determine the molar heat capacity at constant volume and the molar heat capacity at constant pressure.
-
Table illustrates the quantities, marginal costs, average variable costs, and average costs of a competitive firm. Refer to table 4. How much is the unit profit at price =$30? [the problem is based...
-
Suppose that in a risk-neutral world the Vasicek parameters are a=0.15, b = 0.025, and =0.012. The market price of interest rate risk is 0.2. What are the risk-neutral and real-world processes for...
-
Legacy issues $ 325,000 of 5%, four- year bonds dated January 1, 2013, that pay interest semiannually on June 30 and December 31. They are issued at $ 292,181 and their market rate is 8% at the issue...
-
If we have a model for the short rate \(r(t)\), show that (a) the zero coupon bond price can be calculated as: \[P(t, s)=\mathbf{E}_{t}\left[e^{\int_{t}^{s} r(u) d u}...
-
Bower Corporation reported the following information: common stock, $1 par; 50,000 shares authorized; 35,000 shares issued and outstanding. Required: 1. What is the appropriate journal entry to...
-
How much money needs to be set aside every year, for the next 10 years, to purchase a crane? The money is expected to earn 7% interest compounded annually and yearly inflation is expected to be 4%....
-
In a subway station, there are exactly enough customers on the platform to fill three trains. The arrival time of the nth train is X1+ + Xn where X1, X2 . . . are iid exponential random variables...
-
Work Done in a Cyclic Process (a) In Fig. 19.7a, consider the closed loop 1 3 + 2 4 1. This is a cyclic process in which the initial and final states are the same. Find the total work done by the...
-
A gas in a cylinder expands from a volume of 0.110 m3 to 0.320 m3 Heat flows into the gas just rapidly enough to keep the pressure constant at 1.80 X 105 Pa during the expansion. The total heat...
-
Describe a time that you felt unfairly treated and why. How did you respond to the inequity? What other options might you have had?
-
Using the strain-based Morrow fatigue equation (Combination of Coffin-Manson relation and Basquin relation) for combined LCF-HCF fatigue model, find the max allowable strain amplitude for completely...
-
The system shown consists of three cables; 1, 2 and 3. Cable 1 passes over a frictionless pulley. A mass of 7.7 kg is suspended. Determine the force in cable 3 considering the following data: y1 =...
-
b) A motorized winch is shown below. The motor runs at 1350 rpm and the drum is to rotate at 54 rpm. Find the number of teeth that the motor drive gear must have to satisfy this requirement. MOTOR 60...
-
25 lbm of water with a quality value of 0.55 exists in a rigid tank at 80F. Determine the a. The pressure [psia] of the water in the tank (5 points) b. The volume [ft] of the tank (15 points)
-
Consider the mechanical system depicted in the following figure, where m= 1 [kg], b = 2 [N.s/m], and k= k = 1 [N/m]. ellele k m y k ellele b Suppose that y(0) = 0 and y(0) = 1. Obtain the step and...
-
Starting from the Web site of the National Highway Traffic Safety Administration, research the latest studies on the safety of air bags, especially with regard to children. Write a short report...
-
Fill in each blank so that the resulting statement is true. A solution to a system of linear equations in two variables is an ordered pair that__________ .
-
Does the pursuit of employment equity constitute reverse discrimination?
-
Calculating Present Values Imprudential, Inc., has an unfunded pension liability of $645 million that must be paid in 25 years. To assess the value of the firm's stock, financial analysts want to...
-
Describe the operating activities of each company noting similarities and difference between COCA COLA & PEPSICO. Identify two economy wide factors and industry wide factors that could impact on the...
-
The trial balance for a company listed the following account balances at December 31, Year 1, the end of its fiscal year: cash, $36,000; accounts receivable. $31,000; Inventory, $45,000; equipment...
Study smarter with the SolutionInn App