Chapter 9 More About Internet (Class 4)

Chapter 9

More About Internet

C. Answer these questions.

1. What is a web browser? Name any two web browsers.
Ans - Web Browser is a software in your computer which is needed to open the web pages. The two popular web browsers are: Google Chrome and Mozilla Firefox.

2. What is online safety?
Ans - Online safety means being safe while using the Internet.

3. Write any three uses of Internet.
Ans - The three uses of Internet are:

• We can download or play online games.
• We can download movies, songs, games, etc.
• We can book tickets for a train, movies or a flight.

4. Differentiate between downloading and uploading.
Ans- 

Workbook Class 6 Science Chapter 12 Electricity and Circuits

Chapter 12
Electricity and Circuits

Exercise

I. Answer the following questions in brief:

Q.1 How does an electric cell produce electricity?
Ans - Electric cell produce electricity from the chemical stored inside it.

Q.2 How many terminals does an electric bulb have? Can you identify them?
Ans - Electric bulb have two terminals one is positive while the other is negative.

Q.3 Why does a fused bulb not glow?
Ans - In fused bulb the filaments break and current does not pass through it.

Q.4 Is air a conductor of electricity or an insulator? What about the human body?
Ans - Air is a insulator but under certain condition it can conduct electricity. Human body is a good conductor of electricity.

Q.5 Why should the two terminals of an electric cell not be joined directly without connecting them through a device like a bulb?
Ans - The two terminals of the electric cell are never joined together without connecting them thought a switch and a device like a bulb because if we do so the chemical in the electric cell get used up very fast and the cells stops working.

Q.6 How are the terminals of an electric bulb different from those of an electric cell?
Ans - In electric bulb the filament is attached to its two terminals whereas the electricity cell has its two terminals one is called positive while other is called negative.

Q.7 Give any two uses of insulators.
Ans - (a) Insulators are used for covering wires switches

(b) Insulators are used to make hand gloves to hold electrical appliances  

II. Give one term for each of the following:

a) Device to break or complete a circuit - Switch
b) Materials which allow electric current to pass through them. - Conductor
c) Path of electricity to pass - Circuit
d) Thin wire inside electric bulb which glows when current passes through it - Filament
e) Ends of electric bulb or cell. - Terminals
f) Materials which do not allow electric current to pass through them. - Insulators

III. Fill in the blanks:

a) A torch bulb has an outer case of  glass that is fixed on a metallic base.
b) The bulb glows only when current flows through it.
c) A switch is a simple device that either breaks the circuit or complete it.
d) An electric all produces electric from the chemicals stored inside it.
e) When the filament of a bulb breaks, it is said to be fused
f) Both the electric cell and bulb have two terminals each.

IV. State whether True or False

a) An electric bulb has two terminals: one is positive (+) and the other is negative (-). True
b) Human body is an insulator. False
c) The filament of a bulb is made of thick wire. False
d) Handles of a screw driver can be made of metals instead of plastic. False
e) Pure water is an insulator. False
f) We should never join the two terminals of an electric cell directly without connecting them through an electric device. True

V. Match the following:

a) Rubber - (iv)  Insulator
b) Cell - (vi) Positive and negative terminals
c) Switch - (i) Make or break circuit
d) Bulb - (iii) filament
e) Metal - (ii) conductor

VI. Select the Correct alternative:

(i) Gucci and Ricci set up the following apparatuses for showing how a switch works in an electrical circuit. Both the set ups were same except in one way. Gucci used a plywood base while Ricci used an iron base.

Which of the following are true?

Ans (d) Gucci's set up is correct while that of Ricci is not

(ii) Which of these is a conductor?

a) Human body   b) Air Metal    c) Water    d) All of these

Ans (d) All of these

(iii) For making electrical wires, we use the materials which are
Ans (a) conductors

(iv) While demonstrating the working of an electric circuit, the bulb does not glow. This may be because
Ans (d) any of these

(v) Electric current flows
Ans (b) From positive terminal to negative terminal

(vi) The handles of screw drivers are made of
Ans (c) any of these

NCERT Solutions for Class 6 Science Chapter 16 Garbage In Garbage Out

Chapter 16
Garbage In Garbage Out

1. (a) Which kind of garbage is not converted into compost by the redworms?
Ans - Plastic bag and articles, tin glass and aluminium foils are not converted by compost by the red worms.

(b) Have you seen any other organism besides redworms, in your pit? If yes, try to find out their names. Draw pictures of these.
Ans - Earthworms, small insects like ant, millipedes are found in pits.

2. Discuss:
(a) Is garbage disposal the responsibility only of the government?
Ans - No, not just the government, but everybody is responsible for garbage disposal. We should bifurcate wet and dry waste, recycle the non-biodegradable substances and we should also reduce the accumulation of garbage in our house and streets.

(b) Is it possible to reduce the problems relating to disposal of garbage?
Ans - Yes, it is possible to reduce the problems of garbage by scientific disposal of garbage, we can do it by bifurcation of different waste and also by recycling the waste materials.

3. (a) What do you do with the left over food at home?
Ans - Preserve them in refrigerator and use them before they get spoiled.

(b) If you and your friends are given the choice of eating in a plastic plate or a banana leaf plotter at a party, which one would you prefer and why?
Ans - I choose Banana leaf for the following reasons

• Easy to dispose
• Can be reused
• Environment friendly

4. (a) Collect pieces of different kinds of paper. Find out which of these can be recycled,
Ans - All kinds of paper can be used except plastic paper.

(b) With the help of a lens look at the pieces of paper you collected for the above question. Do you see any difference in the material of recycled paper and a new sheet of paper?
Ans - Recycled paper is thick when compared to new sheet of paper.

5. (a) Collect different kinds of packaging material. What was the purpose for which each one mas used? Discuss in groups.
Ans - Different kinds of packaging materials used commonly are:

• Cardboard – used as shoe, soap, bulb and other boxes.
• Plastic Bags – Toys covers, sarees bags, shopping bags, etc.
• Wooden Boxes – Fruit baskets and boxes for hardware.
• Jute Bags – School bags, shopping bags, vegetable bags, etc.

(b) Give an example in which packaging could have been reduced.
Ans - By reusing the packaging material, we can reduce the accumulation of garbage.

(c) Write a story on how packaging increases the amount of garbage.
Ans - The basic purpose of packaging is to protect the product from tampering and to maintain its freshness and purity. However, most of the packaging material is used to beautify the boxes and make them look attractive on the shelves. Unfortunately, a large volume of packaging material goes waste and is thrown into dustbin.
For example, in most of the places, the dustbins are full of chips and biscuit wrappers.
It unnecessarily increases the amount of garbage. It also increases the cost of the product due to unnecessary packaging. We should seriously consider how to reduce unnecessary packaging.

6. Do you think it is better to use compost instead of chemical fertilisers? Why?
Ans 6. Yes, it is better to use compost instead of chemical fertilizers for the following reasons:

• It is easy to prepare compost
• Compost is environment friendly as it does not cause any health issues in humans and animals
• Compost will not cause pollution
• Compost increases soil fertility.
• Compost is biodegradable.

Chapter 7 Internet Services (Class 7)

 

CHAPTER 7

Internet Services

 

A. Tick the correct answer and fill in the blank.

1. URL is the unique link of web pages through which you can open the web page.

2. The mouse pointer changes its shape to and when we move it over a Hyperlink.

3. Data stored on a Cloud storage, can be used from any location that has Internet access.

4. One of the popular chat software is Google Hangouts.

5. Pen command is used to scribble on the web page.

B. Fill in the blanks using the given words.

1. Facebook is the most popular social networking website.

2. Cyberbullying is an act of intentionally threatening, humiliating or embarrassing someone over the Internet.

3. A blogger is someone who writes content for a blog.

4. Hub icon is on the address bar of the browser.

5. Every time a web crawler visits a web page, it makes a copy of it and adds its URL to an index.

C. Classify the names of these websites and write them under correct boxes.

 

E-card	123 greetings
Chatting	googlehangouts
Online shopping	Flipkart
Social Networking	Facebook
Videoconferencing	Skype
Online reservation	irctc

D. Answer in short.

Que 1 What is cloud storage?

Ans - Cloud Storage is networked storage or disk space, available over the Internet.

Que 2 What is inking?

Ans –   Making a note within the browser is called inking.

Que 3 What are crawlers?

Ans – Search engines use automated software known as robots or spiders or crawlers to search the web for the information we are looking for.

Que 4 What is a blog? Give an example of a blogging website.

Ans – Blogs are often made on educational topics, sports, web design, gadgets, tour and travels, cooking etc. A blog typically focuses on a particular subject matter. Some of the popular blogging sites are Blogger.com,Wix.com, Wordpress etc.

E. Answer in detail.

 Que 1 How do you save a picture from a web page to your hard disk?

Ans – To search and save an image–

Step 1: Open a search engine and click on Images option.

Step 2: Type the name of the image. A number of images are displayed.

Step 3: Click on Search Images button.

Step 4: Click on the image to open it.

Step 5: Right-click on the image and select Save picture as option.

 Que 2 What are search engines? How do they work?

Ans –   Search engines are specially programmed websites that are designed to help people find information on the web. They search engine is a special program that searches the web for keywords given by us and displays a list of websites. The most popular search engines are Google, Bing and MSN search. Search engines perform these basic tasks:

*      They search WWW.

*      They select information based on the specified keywords.

*      They keep an index of the words they find, and where they find them.

*      They display users a list of websites that match the keywords found in their index.

 Que 3 Write the difference between upload and download.

Ans - Download is the process of receiving programs or information from the Internet.

         Upload is the process of putting programs or information from our computer on the Internet.

Que 4 How Internet useful in education?

Ans - Internet plays a very vital role in education. In this modern era everyone prefers Google for their queries, problems or doubts. Popular search engines like Google, Yahoo, etc. are the topmost choice of people as they offer an easy and instant reach to the vast amount of information in just a few seconds.This not only makes education cost effective but also saves time. Other than this, teachers use the Internet to supplement their lessons. Internet is like a huge library that is used for information gathering and research.

 Que 5  How is Internet useful in shopping?

Ans – Online shopping means buying and selling products using the Internet. It is a convenient method of shopping in which we can buy or sell anything from our home in just few minutes. It offers a wide range of items to choose from. It saves a lot of time. There is no hassle of waiting in line at the billing counters. Online shopping can be done 24 hours a day and 7 days a week. We do not need to carry cash or travel in bad weather. We can pay through a credit or debit card. Many websites offer the facility of COD (Cash On Delivery), which means pay after the product is delivered at the mentioned address. Some of the online shopping websites are www.flipkart.com, www.amazon.in, www. snapdeal.com, etc.

Que 6  Write any five disadvantages of social networking?

Ans – Disadvantages of social networking:

*      Cyberbullying is a growing problem of using social networking websites. It is an act of intentionally threatening, humiliating or embarrassing someone over the Internet.

*      Many people create fake identities to exploit and abuse others.

*      Confidentiality and privacy are very big issues because people post personal information online.

*      These sites can be very addictive. People use them till late night neglecting their studies, diet and other important work. This affects their health.

*      These sites open up the possibility for hackers to commit fraud or launch and spread viruses.

Chapter 8 More About Visual Basic (Class 8)

 

Class VIII

 

Chapter 8

More About Visual Basic

 

A. Tick the correct answer and fill in the blank.

1. Label  

2. Enable

3. events

4. controls

5. Name

B. Name these controls following tools.

1. Button

2. Check box

3. Textbox

4. Label

5. Rectangle shape

6. Radio Button

 

C. Answer in short.

Que 1. What is the default name of new form added in the Visual Basic?

Ans -  Form1.vb is the default name of new form added in the Visual Basic.

 

Que 2. In which mode do you see the working of your application?

Ans –   In Run mode we see the working of our application .

Que 3. Which event of the command button triggers when user click left mouse button on it?

Ans – Click event of the command button triggers when user click left mouse button on it.

Que 4. What is an event-driven program?

Ans - In an event-driven program, the code of the program gets executed in the response to an event, rather than in the sequence in which they are written. Each action by the user causes an event to trigger.

 

D. Answer in detail.

 

Que 1. What is the use of Properties window in the visual Basic IDE?

Ans - A property refers to the characteristics of an object. The Properties window is use to displays the properties of the selected object. Some commonly used properties are Name, Font, Size, Forecolor, Backcolor, Text, etc. 

             

Que 2. How do you add control on the Visual Basic form?

Ans –   Visual Basic form acts as a background for other controls. We can add controls on the form using two different ways:

*       Select the control to be added on the form by clicking on the tool in the toolbox and then drag it on the form.

*       Double–click the control in the toolbox. It gets added to the top left corner of the current form.

 

Que 3.  Describe any three properties of TextBox control.

Ans –  Three properties of Textbox Control are:

Sn.	Properties	Use
1.	Name	This property sets the name of the TextBox that is used while coding.
2.	Text	This property sets the default text to be displayed in the TextBox.
3.	MaxLength	This property sets the maximum number of characters that a user can type in the TextBox.

 

 

Que 4.  What is Visual Basic? Write any four feature of VB.

Ans –  VB or Visual Basic is a high-level programming language which provides a fast and easy way to create interactive applications. Visual Basic has the following features:

*       It is an event driven language.

*   It provides a collection of mathematical, string and graphical functions.

*       It provides powerful database access controls.

*       It provides useful debugging and error handling tools.

 

Que 5.  What is a form in VB? Describe three of its property.

Ans – The Visual Basic form is used to design an interface by adding various controls on the form using which a user can interact with the application. Like any other control, a form has its own set of properties and events to control its appearance and behaviour.

Sn.	Properties	Use
1.	ForeColor	This sets the color for the text on the form.
2.	BackColor	This sets the background color of the form.
3.	Name	This is used to set the name of the form to refer it.