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Avoid using present continuous tense in the following contexts:

Verbs of perception: See, hear, recognize, taste, smell etc.

Verbs of emotion: Love, hate, wish, desire, hope, prefer, refuse, etc.

Verbs of thinking: Suppose, think, believe, understand, trust, remember, forget, knowing, etc. 

Verbs of possession: Own, possess, contain, etc. 

Examples:

I hate to work from home. [Incorrect sentence]

I hate to work from home.

They are lovling each other.[Incorrect sentence]

They love each other.

She is understanding the problem well.[Incorrect sentence]

She understands the problem well.

Hindus are believing in nature worship.[Incorrect sentence]

Hindus belive in  nature worship.

My brother is wishing to become a doctor.[Incorrect sentence]

My brother wishes to become a doctor. 

I am prefering coffee to tea.

I prefer coffee to tea. 

The soup is tasting spicy.[Incorrect sentence]

The soup tastes spicy.

My uncle is owning two houses.[Incorrect sentence]

My uncle owns two houses. 

The Sun is rising in the East every day.[Incorrect sentence]

The Sun rises in the East every day.

My uncle is going the US frequently.[Incorrect sentence.]

My uncle goes to the US frequently.

Cell biology is a branch of biology which deals with the study of cells.

Cells are building blocks of living organisms and fundamental unit.

Organisms are made up of different types of cells, and cells give structure to the organism. So they are known as a structural unit, cells play biological mechanisms for organisms, so they are known as biological units, and cells play different functions to carry out a life of organisms, so they are known as a functional unit.

Cell theory states that cells are building blocks of organisms, and every cell come from the pre-existing cell.

Relation:  A relation, R, from a non-empty set A to another non-empty set B, is mathematically defined as an arbitrary subset of the cartesian product of A and B. 

Domain, Range and Co-domain of the Relation 

Types of relations: 

1. Empty relation   
2. Universal relation: 
3. Identity relation 
4. Reflexive relation
5. Symmetric relation 
6. Transitive relation
7. Equivalence relation
8.  Inverse relation

Types of Intervals:

• open interval 
• second closed interval  
• open closed interval
• closed open interval

Function: Function is a relation for which each value from set the first component of the ordered pair is associated with exactly one value from the set of second components of the ordered pair.

Important functions

• identity function
• modulus function or absolute value functions
• greatest integer function or integral function or step function
• smallest integer function
• Signum function
• exponential functions
• logarithmic function

 type of functions

• One-One function Or injective function Or injection fashion
• Onto function or subjective functions or surjection function
• One-one onto function or bijective function Or bijection functions
• identity function
• Equal function

You have seen different types.of numbers in the earlier classes 

Eg Natural numbers, whole numbers, integers etc 

When you want to divide a.pizza into 8 equal parts, each person get 1/8 of it. So we need numbers in fractional form.

A number that can be written in the form of p/q where p and q are integers and q shoul.not be equal to zero .( since division with zero is not defined yet)

Question 1: What is the difference Between CO2 and SiO2, hybridization both? 

Answer 1: co2 is the gas, while sio2 is the glass 

Due to c atomic number 6, an electronic configuration is 1s2, 2s2 2p2 

In carbon atom not have d-orbital, and it has 2-sigma Bond and 2-π Bond. So its hybridization is SP, % of s character is 50%, and %of p character 50%. in CO2, have two π-bond, due to π-bond weak Bond. So carbon dioxide is gas and Sio2 is glass because si z= 14  electronic configuration is 1s2, 2s² 2p6, 3s², 3p², 3rd shell have present d- orbital, so it has ( SiO2 ) 4-sigma Bond, sigma Bond is the strong Bond compare π-bond, Co2 is the gas and SiO2 is the glass. Hybridization is sp3.

Looping in C

“The process of repeatedly executing a block of statements is known as looping”.

In looping, a sequence of statements is executed until some conditions for termination of the loop are satisfied. Generally, a program loop consists of two segments: (i)control statement  (ii) Body of the loop.

(i) Control statement tests specified conditions and then directs the repeated execution of the statements contained in the body of the loop.

(ii) Body of the loop is a statement-block, which may consist of one statement or more statements.

The loop may be categories in the following two types depending on the position of the control statements:-

(ii)Exit-controlled Loop: In case of an exit-controlled loop, the control checks the test-condition after executing the body of the loop. Do-while() loop come under this.

(I) Entry controlled Loop: In case of an entry-controlled loop, the control checks the test-condition before entering into the body of the loop. While () and for() loop come under this category.

Now, we are going to discuss, types of loop statements provided by C Language. There are three types:

(a) While() Loop

(b) do-while() Loop

(c) For () Loop 

Light- It is a form of energy which produces the sensation of sight.

Properties of light

• It is an electromagnectic wave.
• Light travels along a straight path that is rectilinear propogation of light.
• Speed of light in vacuum is 3×10⁸ m/s

Three types of beam of light

REFLECTION OF LIGHT

The process of returning back or bouncing back the light to the same medium after striking a surface is called reflection of light.

laws of reflection

1. Incident angle (θ_i) is equal to the reflected angle (θr).

               θ_i=θr

2. Incident ray, Reflected ray and normal to the reflecting surface at the point of incidence lie in the same plane.

• Reflection of silver is highest that is approximately 95%
• reflection of coal is approx. 4%

TYPES OF REFLECTION

REGULAR REFLECTION	DIFFUESD REFLECTION
when a parallel beam of light falls on a smooth and highly polished surface.	when a parallel beam of light falls on a rough surface.
the reflected beam is parallel	the reflected light is not parallel
reflected light is directed in a fixed direction	reflected light spread over wide area
e.g. search lights , polished shoes ,automobile headlights etc.	e.g. light reflected by wooden table ,newspaper etc.