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in a reversible cycle 100 KJ of heat is recieved at 500K then a adiabatic expansion occurs to 400K at which temperature of 50 KJ of heat is recieved , then a further adibatic expansion at 300 K at which temperature of 100 KJ is rejected : (1)find the change in entropy which occurs as the system is restored to its initial state in the remainder of the cycle
The vendor provided 95% pure antimony trioxide [Sb2O3] powder chemical. Molar mass of elements (Sb: 121.8 g/mol; O: 16 g/mol). Solve the following problems to get accurate initial Sb(III) concentration for lab-scale experiments. Hint: The Sb(III) solution needs to be prepared in 1 M HCl solution.
i.How much chemical in mg/L will be required for preparation of 1 g/L Sb(III) stock solution?
ii.What will be the dilution factor to prepare 10 mg/L Sb(III) solution?
Explain why software testing should always be an incremental, staged activity. Are programmers the best
people to test the programs that they have developed?
As software becomes more pervasive, risks to the public (due to faulty programs) become an increasingly
significant concern. Develop a doomsday but realistic scenario in which the failure of a computer program
could do great harm, either economic or human.
A piston–cylinder device contains 1.2 kg of nitrogen gas at 120 kPa and 27°C. The gas is now compressed slowly in a polytropic process during which PV1.3 = constant. The process ends when the volume is reduced by one-half. Determine the entropy change of nitrogen during this process.
The radiator of a steam heating system has a volume of 20 L and is filled with superheated vapor at 200 kPa and 150°C. At this moment both the inlet and exit valves to the radiator are closed. After a while the temperature of the steam drops 40C as a result of heat transfer to the room air. Determine the entropy change of the steam during this process.
1.) A and B are rolling cylinders connecting the shafts S and T. C and E are cylinders fast to these shafts and slipping on each other at P. Find the diameters of C and E if the surface speed of E is twice that of C.
2.) Two solids of right section 2 and 4 are in pure rolling contact between the circular arcs. What is the angular speed ratio for the position shown? Determine the size of the angles , β, and Ø in degrees, and of the radii x and y in inches.
3. Two shafts, having axes in the same plate intersecting at an angle of 45°, turn in opposite senses at 30 rpm and 90 rpm. Draw a pair of cone to be located on these shafts and turn in pure rolling contact. Diameter of base of smaller cone is 1 in. Calculate the cone angles.
4. Two shafts A and B are connected by rolling cones and turn in the same direction. Shaft A makes 300 rpm while shaft B makes 100 rpm. Calculate the cone angle of each cone and the diameter of each base if the base of cone B is 2 in. from the vertex. θ = 30°
1. Two parallel shafts, 11 in. apart and rotating at 75 rpm and 200 rpm, are connected by cylinders in pure
rolling contact. Determine the diameters of the cylinders: (1) when they turn in opposite directions; and (2)
when they turn in the same direction.
2. Two parallel shafts connected by rolling cylinders turn in the same direction 150 rpm and 100 rpm
respectively. The smaller cylinder is 16 in. in diameter. How far apart are the axes of the shafts?
3. Two parallel shafts, 24 inches apart and having a speed ratio of 3, are connected by cylinders in pure rolling
contact. Determine the diameters of the cylinders: (1) when they turn in opposite directions; and (2) when
they turn in the same direction
Consider the following register transfer statements for two 4-bit registers R1 and R2.
PT: R1← R1^ R2
Every time that variable T = 1, either the content of R2 is added to the content of Rl if
x = 1, or the content of R2 is transferred to R1 if x = 0. Draw a diagram showing the
hardware implementation of the two statements. Use block diagrams for the two 4-bit
registers, a 4-bit adder, and a quadruple 2-to-1-llne multiplexer that selects the inputs
to R l . In the diagram, show how the control variables x and T select the inputs of the
multiplexer and the load input of register R1.
As a material engineer in charge of designing concrete mix and facing the following problems, which admixture would you use in each case during mixing or at the jobsite?
a. There is a large quantity of freshly mixed concrete and the work at the jobsite had to stop because of rain.
b. More time is expected to be needed for finishing concrete
c. The structure is subject to freezing
d. Concrete is to be around tightly spaced reinforcing steel
e. Concrete mix will be hauled a long distance
f. High early strength concrete is required, but not necessarily high ultimate strength
