1179 Chapters
Medium 9788131806135

he10-1

Mahesh M. Rathore Laxmi Publications PDF

10

Natural Convection

10.1. Physical Mechanism. 10.2. Definitions—Buoyance force—Volumetric expansion coefficient—Grashof number. 10.3. Natural

Convection Over a Vertical Plate. 10.4. Empirical Correlations for External Free Convection Flow—Vertical plate—Horizontal surfaces

—Inclined plates—Free convection on a long cylinders—Free convection on a spheres. 10.5. Simplified Equations for Air. 10.6. Natural

Convection in Enclosed Spaces. 10.7. Summary—Review Questions—Problems—References and Suggested Reading.

10.1.

PHYSICAL MECHANISM

In natural convection, the fluid motion is due to buoyancy forces within the fluid. The buoyancy forces are developed due to density variation in the fluid caused by temperature difference between the fluid and adjacent surface. The larger the temperature difference in adjacent fluid, the larger the buoyancy force and stronger natural convection currents and higher the heat transfer rate. Whenever a heated object for an example a hot egg, is exposed to atmospheric air, the air adjacent to the hot egg gets heated and becomes lighter (less dense) and thus rises up as shown in Fig. 10.1. This motion leads to the formation of the boundary layer on the surface of the egg and the heat is transferred from the warmer boundary layer to outer atmospheric air by natural convection. The velocity of air is zero at the boundary surface and it is significant outside the boundary layer.

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Medium 9788131804803

pragmc-con

R. K. Jangda Laxmi Publications PDF

C ONTENTS

1. INTRODUCTION TO C AND DATA TYPE ......................................... 1–18

1.1 Overview of C ............................................................................................... 1

1.2 Data Types ................................................................................................... 5

1.3 Data Structures (User Defined Data Types) ................................................. 9

1.4 Type Modifiers ............................................................................................ 10

1.5 Constants ................................................................................................... 12

1.6 Variables .................................................................................................... 14

1.7 Storage Class Specifiers ............................................................................. 15

1.8 Code Fragments Illustrating Various Concepts .......................................... 16

Assignment–A010 ........................................................................................ 17

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Medium 9781944131425

LXCCC-10n.pdf

Ramesh Bangia Laxmi Publications PDF

242

Light Pens 6

Line Printers 8

Line Up Icons 63

M

Mailcity 183, 191

Mechanical Mouse 5

Media Clip 211

Modem 182

Mouse Pad 5 multiuser system 181

N

Non-Impact Printers 8

Non-impact Printers 7

Normal view 212

Notes Page view 212

Num Lock 4

Numeric Keys 4

O

OLE Object 66

Open Files 61

Optical Disks 16

Optical Mouse 5

Optomechanical Mouse 5

Output Unit 2

P paper size 79 paper source 79

Presentation Templates 210

Preview 85

Primay Storage 2

Printers 7

Private Networks 151

Projector Wizard 233

Public Networks 151

Q

Quick Launch Toolbar 55

QWERTY 4

R

RAM 10

Course on Computer Concepts (CCC)

Rediff 183, 191

Rehearse Timings 234

Resume Wizard 82

ROM 9

Routers 150

S

Screen Image 65

Slide Master 228

Slide Show 206, 233

Slide Show view 212

Slide Sorter view 212

Slide Transition 230

Small Icons 62

Smilies 195

Sort Order 61

Stars and Banners 228

Sum Function 116

T

Telnet 154

Touch Pad 7

Touch Screens 6

Trackball 6 transistor 2, 18

U

UNIVAC 2

USB Thumb Drive 17

Usenet 154, 157

V vacuum tube 2, 18

W

Web Page 158

Web Server 158

Web Site 158

Width of a Column 112

WinZip 56

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Medium 9789381159507

oops-11.pdf

Hari Mohan Pandey Laxmi Publications PDF

CHAPTER

11

INPUT-OUTPUT AND

MANIPULATORS IN C++

11.1 INTRODUCTION

In all the earlier chapters, we have worked with cin and cout for taking all different types of data as input and displaying them. But, we have not worked with the formatted output i.e., the way we want to print the data onto screen. For managing the input and output operations C++ provides the concept of stream classes. We know that cin is treated as standard input stream and cout as standard output stream classes. We known that cin is treated as standard input streams and cout as standard output streams. A stream is termed as input stream and when data is sent by the program to the output device say screen, the stream termed as output stream. It is quite obvious as we have seen in almost all the C++ programs so far that to take data from keyboard we have cin, which receives data and display s onto the screen. Thus, cin is standard input stream and cout is standard output stream.

We have also said that >> is an extraction operator <> extraction data from input stream from input stream and cout << displays inserts data into output stream. C++ provides numbers of stream classes for the efficient handling input and output and which is our next topic of discussion.

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Medium 9789380856667

ch3-1

Dr. R. K. Bansal Laxmi Publications PDF

3

Properties of Surfaces and Solids

3.1. CENTROIDS AND CENTRE OF MASS

The point at which the total area of a plane figure (like rectangle, square, triangle, quadrilateral, circle etc.) is assumed to be concentrated, is known as the centroid of that area.

The centroid is also represented by C.G. or simply G.

Centre of mass is the point at which the total mass of a body, is assumed to be concentrated. A body is having only one centre of mass for all positions of the body.

3.1.1. Centroid of Simple Plane Figures. (i) The centre of gravity (C.G.) of a uniform rod lies at its middle point.

(ii) The centre of gravity of a triangle lies at the point where the three medians* of the triangle meet.

(iii) The centre of gravity of a rectangle or of a parallelogram is at the point, where its diagonals meet each other. It is also the point of intersection of the lines joining the middle points of the opposite sides.

(iv) The centre of gravity of a circle is at its centre.

3.1.2. Centroid of Areas of Plane Figures by the

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