CBSE Class 9 - Chemistry - Structure Of Atom (Worksheet) (#cbsenotes)(#eduvictors)

CBSE Class 9 - Chemistry
 - Structure Of Atom
(Worksheet)

An atom is the smallest indivisible unit of an element.. Modern chemistry began with eighteenth-century discoveries leading to the formulation of two basic laws of chemical combination, the law of conservation of mass and the law of constant composition (definite proportions). Later it led to the development of various atomic models and discoveries of sub-atomic particles. Here is a worksheet based on NCERT Chapter 4 to assess your knowledge about structure of atoms.

Class 9 - 12 - Biology - Know About Disease - Brief Notes About AIDS (#cbsenotes)(#eduvictors)

AIDS(A Brief Introduction)

Meaning of AIDS

✤ The word AIDS stands for Acquired Immuno Deficiency Syndrome. This means a deficiency of the immune system, acquired during the lifetime of an individual indicating that it is not a congenital disease [disease or abnormality present from birth]. ‘Syndrome’ means a group of symptoms.


✤ AIDS was first reported in 1981 and in the last twenty-five years or so, it has spread all over the world.

✤ Luc Montagnier, Françoise Barré-Sinoussi, and their colleagues at the Pasteur Institute in Paris were the first to report the discovery of the virus now called the human immunodeficiency virus (HIV) associated with AIDS.


Causes of AIDS

CBSE Class 12 - 9 - How Good Your are in Physics? - Simple Physics Quiz (1 Word Answers)(#cbsenotes)(#eduvictors)(#physicsquiz)

Physics Quiz (1 Word Answer)

Q1: Who firstly demonstrated experimentally the existence of electromagnetic wave?

Q2: The working of the quartz crystal in the watch is based on which effect?

Q3: What is the unit of Radioactivity?

Q4: What is the wavelength of the visible spectrum?

Q5: One astronomical unit is the average distance between___?

Q6: Number of basic S.I. units are ___.

Q7: What is the name of the scientist who stated that matter can be converted into energy?

Q8: The size of the atomic nucleus is of the order of___?

Q9: A temperature at which both the Fahrenheit and the centigrade scales have the same value?

Class 12 - Physics - ELECTROMAGNETIC WAVES AND OPTICS - About Electromagnetic Spectrum? (#cbsenotes)(#eduvictors)

Class 12 - Physics - ELECTROMAGNETIC WAVES AND OPTICS - 

About Electromagnetic Spectrum 

Electromagnetic Spectrum
credits: wikimedia, author: penbaug 

Name	Wavelength range	Production	Uses
Gamma Rays	10⁻ⁱ²m	Gamma rays produced in the radioactive decay of the nucleus	In the treatment of cancer and to carry out nuclear reactions.
X-Rays	10⁻⁹m - 10⁻ⁱ²m	x-rays tubes or inner shell electrons	Used as a diagnostic tool in medical to find out fractures in bones. to find cracks, flaws in the metal part of a machine
UV Rays	4×10⁻⁷m - 10⁻⁹m	By very hot bodies like the sun and by UV lamps.	In water purifier in the detection of forged documents, in food preservation.

CBSE Class 10 - Science - Chapter 14 - Sources Of Energy - Study Points (#eduvictors)(#cbsenotes)

Class 10 - Science - Chapter 14 

Sources Of Energy 

Study Points

Energy:  

Whenever a body is capable of doing work, the body is said to possess energy. Thus energy is defined as the ability of a body to do work and the amount of energy possessed by a body is equal to the amount of work it can do when its energy is released.

Energy comes in different forms and one form can be converted to another. For example, if we drop a plate from a height, the potential energy of the plate is converted mostly to sound energy when it hits the ground.

A good source of energy should be:

i) Safe and convenient to use, e.g., nuclear energy can be used only by highly trained engineers with the help of nuclear power plants. It cannot be used for our household purposed.

ii) Easy to transport, e.g., coal, petrol, diesel, LPG etc. Have to be transported from the places of their production to the consumers.

iii) Easy to store, e.g., huge storage tanks are required to store petrol, diesel, LPG etc.

Class 8 - Science - Combustion and Flame - Study Points (#cbsenotes)(#eduvictors)

CBSE Class 08 Science 

Study Points

Chapter 6: Combustion and Flame

⑴ Combustion: The process of burning a substance in the presence of air (oxygen) and undergoes a chemical reaction to produce heat and light.

⑵ The substances which burn in the air are called combustible.

⑶ Oxygen (in air) is essential for combustion.

⑷ During the process of combustion, heat and light are given out.

⑸ Ignition temperature is the lowest temperature at which a combustible substance catches fire.

⑹ Types of combustion: The type of combustion differs depending on the type of fuel. Based on nature and intensity, combustions are classified into three types. They are:
        (i) Rapid combustion
        (ii) Spontaneous combustion
        (iii) Explosion

⑺ The calorific value of a fuel is expressed in kilojoules per kilogram (kJ/kg).

Class 9 - FIT - Chapter 02 - Computer System Organisation - Very Short Answer Type Questions (#cbsenotes)(#eduvictors)

Computer System Organisation

Very Short Answer Type Questions

Q1: Name the most commonly used input device.

Answer: Keyboard is the most commonly used input device, which can also be used to type commands directing the computer to perform certain actions.


Q2: Explain the main advantage and disadvantage of an OCR?

Answer: The main advantage of an OCR is the ability to scan the characters accurately. The disadvantage of an OCR is the limited number of characters offered by it.


Q3: Why do we use a webcam?

Answer: A webcam is basically used for capturing a series of digital images that are transferred by the computer to a server and then displayed to the hosting page.


Q4: Name the memory (Primary/Secondary)with the following features:

• If the current is interrupted, data is lost.
• Before a program is ready to run, the program is loaded into this memory, which allows the CPU to directly access the program.