गुरुत्वाकर्षण (Gravitation)

गुरुत्वाकर्षण (Gravitation)

 सर आयझॅक न्यूटन ने गुरुत्वाकर्षण की खोज की, यह आपको पता ही है । ऐसा कहा जाता है कि वृक्ष से नीचे गिरता हुआ सेब देखने के कारण उन्होंने यह खोज की । उन्होने सोचा कि सभी सेब (लंबवत दिशा में) सीधे नीचे ही क्यों गिरते हैं? तिरछे क्यों नही गिरते? या क्षितिज के समांतर रेखा में क्यों नहीं जाते?

अत्यंत विचारमंथन करने के पश्चात्उन्होंने निष्कर्ष निकाला की पृथ्वी सेब को अपनी ओर आकर्षित करती होगी और इस आकर्षण बल की दिशा पृथ्वी के केंद्र की ओर होगी । वृक्ष के सेब से पृथ्वी के केंद्र की ओर जानेवाली दिशा क्षैतिज के लंबवत होने के कारण सेब वृक्ष से क्षैतिज के लंबवत दिशा में नीचे गिरता है ।

गुरुत्वाकर्षण बल की कल्पना और सेब एवं चंद्रमा पर लगनेवाला गुरुत्वीय बल 

 आकृति  में पृथ्वी पर सेब का एक वृक्ष दिखाया गया है । सेब पर लगनेवाला बल पृथ्वी के केन्द्र की दिशा में होता है अर्थात सेब के स्थान से पृथ्वी के पृष्ठभाग पर लंब होता है । आकृति में चंद्रमां और पृथ्वी के बीच का गुरुत्वाकर्षण बल भी दिखाया गया है । (आकृति में दूरियाँ, पैमाने के अनुसार नहीं दिखाई गई हैं । )

्यूटन ने सोचा कि यदि यह बल विभिन्न ऊँचाई पर स्थित सेबों पर प्रयुक्त होता है, तो क्या वह सेबों से बहुत दूर स्थित चंद्रमा जैसे पिंडो पर भी प्रयुक्त होता होगा? इसी प्रकार क्या यह सूर्य, ग्रह जैसे चंद्रमा से भी अधिक दूरी पर स्थित खगोलीय पिंडों पर भी प्रयुक्त होता होगा?

 

गुरुत्वीय स्थितिज ऊर्जा (Gravitational potential energy)

गुरुत्वीय स्थितिज ऊर्जा (Gravitational potential energy)

पिंड की विशिष्ट स्थिति के कारण या स्थान के कारण उसमें समाविष्ट ऊर्जाको स्थितिज ऊर्जाकहते हैं । यह ऊर्जा सापेक्ष होती है और पृष्ठभाग से पिंड की ऊँचाई बढ़ने पर वह बढ़ती जाती है, इसकी जानकारी हम प्राप्त कर चुके हैं । m द्रव्यमान तथा पृथ्वी के पृष्ठभाग से h ऊँचाई पर स्थित पिंड की स्थितिज ऊर्जा mgh होती है और पृथ्वी के पृष्ठभाग पर वह शून्य होती है, ऐसा हमने देखा है । h का मान पृथ्वी की त्रिज्या की तुलना में अत्यंत कम होने के कारण g का मान हम स्थिर मान सकते है और उपर्युक्त सूत्र का उपयोग कर सकते हैं । परंतु h का मान अधिक होने पर g का मान ऊँचाई के अनुसार कम होते जाता है । पिंड पृथ्वी से अनंत दूरी पर होने पर g का मान शून्य होता है और पिंड पर पृथ्वी का गुरूत्वीय बल कार्य नहीं करता । इस कारण वहाँ पिंड की गुरूत्वीय स्थितिज ऊर्जा शून्य मानी जाती है । अतः दूरी उससे कम होने पर स्थितिज ऊर्जा ऋण होती   है ।   

 

  पिंड पृथ्वी के पृष्ठभाग से h ऊँचाई पर स्थित होने पर उसकी गुरूत्वी स्थितिज ऊर              

  GMm     

  R + h              के बराबर होती है। यहाँ M और R पृथ्वी के द्रव्यमान तथा त्रिज्या है ।                 

गुरुत्वीय लहरें (Gravitational waves)

गुरुत्वीय लहरें (Gravitational waves)

 पानी में पत्थर डालने पर उसमें लहरें निर्मित होती हैं, इसी प्रकार एक रस्सी के दोनों सिरों को पकड़कर हिलाने पर उसपर भी लहरे निर्मित होती हैं, यह आपने देखा ही होगा । प्रकाश भी एक प्रकार की तरंग है, उसे विद्‌युतचुंबकीय तरंग कहते हैं । गामा किरण, क्ष- किरण, पराबैंगनी किरण, अवरक्त किरण, माइक्रोवेव्ह और रेडिओ तरंग ये सभी विद्‌युतचुंबकीय तरंग के ही विविध प्रकार हैं । खगोलीय पिंड ये तरंगे उत्सर्जित करते हैं और हम अपने उपकरणों द्‌वारा उन्हें ग्रहण करते हैं । विश्व के बारे में संपूर्ण जानकारी हमें इन तरंगों के द्‌वारा प्राप्त हुई है । गुरूत्वीय तरंगे एकदम अलग प्रकार की तरंगे हैं, उन्हें अंतरिक्ष काल की तरंगे कहा जाता है । उनके अस्तित्व की संभावना आईनस्टीन 1916 में व्यक्त की थी । ये तरंगें अत्यंत क्षीण होने के कारण उन्हें खोजना अत्यंत कठिन होता है । खगोलीय पिंडों में से उत्सर्जित गुरूत्वीय तरंगों को खोजने के लिए वैज्ञानिकों ने अत्यंत संवेदनशील उपकरणों को विकसित किया है । इसमें LIGO (Laser Interferometric Gravitational Wave Observatory.) प्रमुख है । वैज्ञानिकों ने सन 2016 में आईनस्टाईन की भविष्यवाणी के 100 वर्षों के पश्चात गुरूत्वीय तरंगो की खोज की । इस शोध में भारतीय वैज्ञानिकों का योगदान है । इस शोध के द्‌वारा विश्व की जानकारी मिलने के लिए एक नया मार्ग खुल गया है ।

फ्लेमिंग का बाएँ हाथ का नियम (Fleming’s left hand rule)

फ्लेमिंग का बाएँ हाथ का नियम (Fleming’s left hand rule)

उपर्युक्त प्रयोग में हमने विद्‌युत धारा की दिशा और चुंबकीय क्षेत्र की दिशा दोनों की ओर ध्यान दिया और ऐसा दिखाई दिया की बल की दिशा इन दोनों के लंबवत हैं । इन तीनों की दिशा एक सरल नियम के द्‌वारा सुबद्ध की जा सकती है । इस नियम को ही फ्लेमिंग के बाएँ हाथ का नियम कहते हैं । इस नियम के अनुसार बाएँ हाथ के अंगूँठे, तर्जनी और मध्यमा को एक दूसरे के लंबवत रखे और यदि तर्जनी चुंबकीय क्षेत्र की दिशा में हो, मध्यमा विद्‌युतधारा की दिशा में हो तो अंगूठे की दिशा विद्‌युत चालक पर बल की दिशा दर्शाती है ।

 

पर्यावरण संवर्धन तथा जैवविविधता (Environmental conservation and Bio-diversity)

पर्यावरण संवर्धन तथा जैवविविधता (Environmental conservation and Bio-diversity)

पर्यावरणीय प्रदूषण का सबसे घातक परिणाम सजीवोंं पर होता है । आपके आसपास (परिसर में ं) इस प्रकार की घटनाओं को क्या आपने देखा है? पृथ्वीपर हमारी सजीवसृष्टि यह विविधताओं से भरी पड़ी है । इसमें विविध प्रकार की वनस्पतियों तथा प्राणियों का अस्तित्व था । आज हम देखते हैं की अपने पिछली पीढियों द्वारा सुने गए ऐसे विशिष्ट प्राणी देखने को नहीं मिलते । इसके लिए जिम्मेंदार कौन? प्रकृति में पाए जानेवाले एक ही जाति के सजीवोंं में व्यक्तिगत तथा आनुवांशिक भेद, सजीवोंं की जातियों के विविध प्रकार तथा विविध प्रकारों की परिसंस्थाएँ इन सभी के कारण उस स्थान पर प्रकृति को जो सजीवसृष्टि की समृद्धी प्राप्त हुई है उसे ही जैवविविधता कहते है । जैवविविधता यह तीन स्तरों पर दिखाई देती है ।

आनुवंशिक विविधता ः (Genetic Diversity) 

एक ही जाति के सजीवोंं में पाई जाने वाली विविधता को आनुवांशिक विविधता कहते है। उदा. प्रत्येक मनुष्य दूसरे की अपेक्षा थोड़ा भिन्न होता है। पुनरुत्पादन प्रक्रिया में सहभागी होनेवाले सजीवोंं में ये आनुवांशिक विविधता कम हुई तो धीरे-धीरे उस जाति के नष्ट होने का खतरा बना रहता है । 

प्रजातिंकी विविधता (Species Diversity)

एक ही प्रदेश में एक ही प्रजाति के प्राणियों में अथवा वनस्पतियों में भी विविध जातियॉं दिखाई देती है, उसे ही प्रजातियों की विविधता कहते हैं । प्रजाति विविधता में वनस्पती, प्राणी तथा सूक्ष्मजीव इनके विविध प्रकारों का समावेश होता है ।

परिसंस्था की विविधता (Ecosytem Diversity)

प्रत्येक प्रदेश में अनेक परिसंस्थाओ का समावेश होता हैं । किसी प्रदेश के प्राणी तथा वनस्पती, उनका अधिवास तथा पर्यावरण में अंतर इनके संबंधो से परिसंस्था की निर्मिती होती है । प्रत्येक परिसंस्था के प्राणी, वनस्पती, सूक्ष्मजीव और अजैविक घटक भिन्न-भिन्न होते हैं । अर्थात प्राकृतिक तथा मानवनिर्मित इस प्रकार की भी दो स्वतंत्र परिसंस्थाऍं होती है । 

 Business management

Types of business management

There are nearly two dozen branches of business management. Here is an overview of the 22 sectors in this wide field:

1. Financial management

Financial management deals with finding a healthy balance between profit and risk so that even with a setback, the business is profitable in the long term. This type of business management involves planning, directing and coordinating with the accounting, investing, banking, insurance, securities and other financial activities of a business.

The three key elements of financial management are financial planning, financial control and financial decision making. Short-term financial management is often referred to as "working capital management" and relates to cash management, inventory management and debtor management. Both the assessment and technique of financial decisions fall under this type of business management.

2. Marketing management

Marketing management focuses on the practical application of marketing techniques and the management of a company's marketing resources and activities. The four major areas of marketing management are company analysis, collaborator analysis, competitor analysis and customer analysis. Marketing management also includes brand management, as well as marketing strategy and pricing.

To maximize return on investment, it's essential to develop branding opportunities and to execute marketing tactics based on careful analysis of all aspects of your business. The scope of a business's marketing management depends on a business's size and industry. Effective marketing management uses a company's resources to increase its customer base, improve customer outlook and feedback, and increase the company's perceived value.

3. Sales management

Sales management involves overseeing and leading sales teams. As a sales manager, you drive your sales reps to foster strong relationships  with prospects, convert them to leads and move them through the sales pipeline. Sales management often works hand in hand with marketing management.

4. Human resource management

Human resource management (HRM) focuses on the recruitment and management of an organization's employees. This includes compensation, hiring, safety and wellness, benefits and other aspects of employee administration.

A common misconception about HRM is that it's solely the responsibility of a human resources department or individual. In reality, all department managers should understand that effective HRM enables employees to contribute effectively and productively to the overall direction and goals of the company. In the past, HRM focused more on personnel administration, but a modern HRM approach uses employee programs to make a positive impact on both the staff and the business as a whole.

5. Strategic management

Strategic management is the application of strategic thinking to the job of leading an organization. Many of the other branches of business management revolve around strategic management, because the success of a business is often determined by financial, marketing and operational strategies.

Strategic management focuses on the big picture of a business: Where do you want to be, and how can you get there? Strategic management is adaptive, incorporates a competitive strategy and keeps an organization relevant. The most important element of strategic management is the formulation of the organization's goals, taking into account external factors such as regulation, competition and technology.

6. Production management

Production management is the decision making involved in the manufacturing of products or services. Production management techniques are used in both manufacturing and service industries. This type of business management is about converting raw materials into a finished product or service, and as such, this sector often references the "four M's": machines, methods, materials and money.

One of the main focuses of production management is ensuring that production is efficient, and this includes inventory control and employee training. Inventory control is by far the most important responsibility of product managers and involves tracking all components of production, such as required materials and finished goods.

Another major focus of a business's production management team is the research and development (R&D) of both the production process and the product itself. Businesses looking to expand, cut costs and develop newer and better products must conduct R&D as a part of their product management.

7. Program and project management

Project management is the planning, execution and supervision of projects. Project managers prioritize obtaining the tools or knowledge needed to fulfill both short-term and long-term project requirements. Program management is similar: It involves the same task for many projects, not just one.

8. Knowledge management

Knowledge managers create, distribute and manage a company's knowledge. Project managers may turn to knowledge managers when their projects call for information that would be difficult to find elsewhere.

9. Operations management

Operations management is the responsibility for ensuring that all departments of business operations are efficient. Managing the operations of a business means dealing with a plethora of departments, strategies and processes. Operations teams need to consider the acquisition, development and utilization of resources their business needs to deliver the goods and services clients want.

10. Service management

Service management varies widely depending on the industry and the business. Sometimes, it's synonymous with IT service management, but the two sectors differ in a few areas. First, service management usually incorporates both automated systems and skilled labor and often provides service development, even if it is not IT related.

One focus of service management is the managing and streamlining of workflow to automate or support human decision making. Service management is what enables a provider to understand its services from both the organization's and the consumer's perspective and to ensure that the services facilitate the desired outcomes of their clients. No matter the service, managed-service providers need to understand and manage the costs and risks involved, as well as the value and importance of the services to their clients.

11. IT management

IT management focuses on overseeing and handling the technology resources of a business to meet its needs and priorities. IT managers and teams ensure a business's technology is aligned with the company's strategies. The three key elements of IT management are IT configuration, IT service and IT financial management.

IT management also involves meeting business goals while fulfilling customer expectations. IT managers must focus on individual components and the delivery of end-to-end services using the best methods for reducing costs and improving employee efficiency. IT management incorporates the education and development of managers who can effectively manage the planning, design, selection, implementation, use and administration of emerging and converging information and communications technologies.

12. Public relations management

In public relations management, you communicate with public figures, primarily journalists, who can inform the public about your company's latest news, products and more. Public relations strategies may vary by industry, but they have a consistent end goal: a strong public image.

13. Supply chain management

Supply chain management is the oversight of how raw materials move from manufacturers, wholesalers or other starting points to your business. Your business ultimately uses these raw materials to create its products.

14. Procurement management

Like supply chain management, procurement management can involve the acquisition of products from another entity. It may also involve arrangements for services from third-party providers, and its focus is typically more on budgetary limits and deadlines than on the supply chain.

15. Research and development management

An R&D manager oversees the product research and development efforts of a team or an entire company. R&D managers may manage researchers and developers, conduct research and development tasks themselves, or perform both of these roles.

16. Engineering management

Engineering management and R&D management are among the types of management with the most overlap. Engineering management may involve more manufacturing – turning research into sellable items – than R&D management, but often, these two types of management entail similar tasks.

17. Design management

Like R&D management, design management is the oversight of how products evolve from an idea to a tangible item. However, design managers may focus equally on an item's appearance and functionality, whereas R&D managers often prioritize function over form.

18. Quality management

Quality management is the oversight of all quality assurance tasks. It often involves product or service planning. After customers or clients first use the product or service, a quality manager will assess the improvements that users seek and guide the team through implementing these changes.

19. Risk management

Risk management involves assessing business practices and identifying problem areas. Once potential flaws are identified, risk managers consult company executives and other department heads to discuss how these risks can be minimized.

20. Change management

Change management is a broad type of management that addresses a wide variety of company transitions, whether internal or external. Change management may entail guiding teams through policy changes or the implementation of new teams. It can be as broad as assisting with company mergers and acquisitions.

21. Innovation management

Innovation management is the oversight of several other types of management. Innovation managers may work to coordinate the tasks of R&D, strategic and change managers in order to streamline work toward overarching company goals.

22. Facility management

As with other types of management, resource allocation plays a key role in facility management. However, with facility management, the resource in question is usually a full building, such as an office or data center.

Computerized Accounting

 Manual accounting for thousands of years had been the trend and standard until around 1980s when fast computers hit the market globally. Computers for diverse functions were not only found to be reliable, highly accurate and the easiest to use in accounting circles but made it so easy to store and manage tons of financials data. With accounting software today allowing small businesses, governmental bodies to individuals to basically accomplish any type of accounting function computerized accounting continue to pack lots of unique features. The following are all the important information about computerized accounting.

The Definition of Computerized Accounting

Accounting in itself is the system made up of diverse controls, processes and procedures for the summarization, classification, recording and collection of financial data to help businesses, individuals, governments and other entities make decisions and interpret it to understand their financial status. Computerized accounting is carried out via computerized accounting software and computers in the recording, analysis and storage of financial and accounting data. With all manner of systems available today, small businesses and anyone else can actually find the computerized accounting system that matches their individual characteristics.

Financial transactions of an organization today are wholly recorded in computerized accounting programs with an entry largely made once transactions are finished. All the information is recorded in the computerized accounting system; due to the development of cloud storage and systems it's actually easier to connect a businesses' computerized program with the cloud and back up all financial information in real-time to safeguard against system crashes without any warning. Backups are also carried out in internal and external backup systems to keep this vital data intact.

The Advantages of Computerized Accounting and Features

The advantages of computerized accounting and features are aplenty. Some of the special benefits for going for a computerized accounting system include:

Automation: Computerized accounting has picked up due to the nature of paperwork, which is cumbersome, tiring and time consuming. Computerized systems bring to an end most time-consuming and mundane accounting tasks related to manual paperwork management of financial data. Highly accurate-Computerized accounting is so accurate the possibility of an error is virtually impossible. After imputing financial data from subtractions, additions to complex calculations every process is software completed automatically.

Access to information: Before computerized accounting systems collaborating with co-workers remotely in real-time and sharing financial information and data was wholly impossible. Accounting software and computers allow users to share financial information in real-time whether on mobile devices like Tablets or desktops through different methods including cloud-based web systems.

Reliable: The accuracy of diverse financial statements through computers has led to improvement of accounting tools and reliability of financial accounting statements.

Scalability: As small businesses grow and complexity of accounting required becomes more intense computerized accounting ensures nothing really limits performance and processes of the business; accounting software and complex computers keep the processes fast, reliable and easier to carry out.

Secure: With external and cloud-based storage choices data is safely stored averting losses from earthquakes, floods, and arsons to accidents. Features of computerized accounting system are diverse too. Whether you've done an intensive computerized accounting course or not you can actually carry out accounting through any computer system. Computerized accounting is top-notch enough to handle lots of transactions at the same time accurately and speedily.

You can also carry out real-time and instant reportage providing much needed quality financial accounting reports and accurate and reliable data. The age of complete manual system with lots of paper documents is virtually gone. No more need for vouchers, receipts, journals, books and records to complete accounting processes.

With such features as OCR (optical character recognition) in PDFs you can actually transform all your financial documents from receipts to invoices into searchable and editable PDF document fast. Computerized accounting systems ensure vital, complete and needed accounting reports are produced fast and as expected.