Mystery of Earth not revolving around the Moon

There is a famous saying by Newton, “What we know is a drop; what we don’t know is an ocean.” This great physicist of all time is a true genius ever to be born. He gave us the famous law of gravitation, the laws of motion, calculus and much more to cherish. Although there is a lot to learn from Newton, we will aim to understand the motion of the moon around the earth in the lines which follow.
We all know that the moon revolves around the earth, but what makes it revolve around the earth, and why wouldn’t the earth revolve around the moon? Or say, why wouldn’t just like the earth, the moon revolve around the sun? Why do the planets revolve around the sun, and why do the moons of planets revolve around that particular planet only? Baffling questions which make us wonder about the celestial bodies and their behavior. So, let’s get to the bottom of the problem and try to figure out how these astronomical bodies have been working perfectly and constantly day in and day out for millions of years.
This system of the moon revolving around a planet is based on the concept of center of mass. But what is center of mass? Well, the center of mass is the point around which two planets have their orbits.
If two bodies have equal masses, then the center of mass is located in the middle of them. This is the case with Pluto and its natural satellite Charon. It’s also the case of binary asteroids and the stars. But if one of the bodies is heavier than the other, then the center of mass shifts closer to the heavier body. Just like in the earth–moon system, the earth is much heavier as compared to the moon, and as a result, the center of mass of the earth–moon system lies inside the earth at a distance of about 4300 km—which is approximately 75% of the earth’s radius—from the center of the earth. So, we are unable to see the orbital motion of the earth around the center of mass, but the moon is at a considerable distance from the center of mass of the earth–moon system. Hence, its orbital motion is quite visible.
Now let’s come to the question of why the moons of different planets are still revolving around their planet and not attracted towards the sun, which is much more massive than the planets. The law of gravitation says that the larger the mass of the object, the greater would be the force of attraction between the objects. Interestingly, the sun contains about 99.8% mass of the solar system. So, shouldn’t it be able to snatch the moon away from the earth? It’s true that the sun attracts the moon with twice the gravitational force as compared to the earth, yet the moon doesn’t leave the earth but continues to faithfully orbit around it. This happens because every planet has a region with which it dominates the attraction of its satellite. This special region is called the hill sphere. So, to be retained by a planet, a moon should lie within the planet’s hill sphere. In more precise terms, the hill sphere approximates the gravitational sphere of influence of a smaller body when faced with perturbation from a more massive body. The hill sphere of the earth is about 1.5 million km and the moon revolves around the earth at about 0.384 million km. So, our beloved moon is not going to be pulled by the sun. It’s safely ours. This same theory applies to every planet and its many moons.

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Android app pass data between activities

Passing Data types like String, Integer, Float, double is quite easy in android so we don’t need any special class for this. But for Android pass model from intents using Serializable from intents we need Serializable class.

What is Modal Class

Model can be applied to a class which represents your application’s data model, and will cause instances of the class to become observable, such that a read of a property of an instance of this class during the invocation of a composable function will cause that component to be “subscribed” to mutations of that instance. Composable functions which directly or indirectly read properties of the model class, the composables will be recomposed whenever any properties of the the model are written to.

What is Serializable?

It is a standard Java interface. So you can just implement Serializable interface and add override methods.

There are pros and cons of this class. It is comparatively slow and easy to integrate.

To immplements simple Data types we can just pass ‘Xyz’ by key ‘name’.

Intent intent = new Intent(MainActivity.this, DataActivity.class);
intent.putExtra("name","Xyz");// for string variable 

And in data activity to fetch the data by key ‘name’.

Intent intent = getIntent();
intent.getStringExtra("name");// to fetch data

But for passing objects or model class we need serialization.

So let’s get started on how Android app pass data between activities.

For this section I have created MainActivity, DataActivity and UserModel to achieve the task.

To send the model class from MainActivity to DataActivity class by using Serializable class.

package com.example.sampleproject;


import android.content.Intent;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;

public class MainActivity extends AppCompatActivity {

    protected void onCreate(Bundle savedInstanceState) {

        ((Button)findViewById( View.OnClickListener() {
            public void onClick(View v) {
                UserModel mUser = new UserModel();

                Intent intent = new Intent(MainActivity.this, DataActivity.class);
                intent.putExtra("user", mUser);


To fetch the model class from main activity.

package com.example.sampleproject;

import android.content.Intent;
import android.os.Bundle;


import androidx.appcompat.widget.Toolbar;

import android.util.Log;
import android.view.View;


public class DataActivity extends AppCompatActivity {

    private String TAG = "DataActivity";

    protected void onCreate(Bundle savedInstanceState) {
        Toolbar toolbar = findViewById(;

        FloatingActionButton fab = findViewById(;
        fab.setOnClickListener(new View.OnClickListener() {
            public void onClick(View view) {
                Snackbar.make(view, "Replace with your own action", Snackbar.LENGTH_LONG)
                        .setAction("Action", null).show();

        Intent intent = getIntent();
        if (intent != null) {

            Serializable s = intent.getSerializableExtra("user");
            UserModel mUserModel = (UserModel) s;
            if(mUserModel!=null) {
                int id = mUserModel.getId();
                String name = mUserModel.getName();
                String mobile = mUserModel.getMobile();
                Log.d(TAG, "id: "+id);
                Log.d(TAG, "name: "+name);
                Log.d(TAG, "mobile: "+mobile);
            }else {



Model which is shared between the MainActivity and DataActivity class.

You can also add child model or list of UserModel class just you have to implements that model by Serializable.

package com.example.sampleproject;


public class UserModel implements Serializable {

    private int id;
    private String name;
    private String mobile;

    public void setId(int id) { = id;

    public int getId() {
        return id;

    public void setName(String name) { = name;

    public String getName() {
        return name;

    public void setMobile(String mobile) { = mobile;

    public String getMobile() {
        return mobile;

Output of Android app pass data between activities:

The output of this code will look like this.

id: 1.
name: Xyz.
mobile: 99919290XX.

You can also see this post where I have passed a model class between activities by using intents from here.

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Colors is the visual feeling which is corresponding in humans to the categories called red, yellow, blue and other properties of color are.

  • The physical specification of color are associate with objects, materials and light sources based on their physical properties like light absorption and reflection are the properties of colors.
  • There are 3 dimensions of colour hue, value and intensity or chroma.
  • It is a major concern in all aspects.
  • It is calmingly an increasingly important part of modern living.
  • There are two things an external occurrence and an internal sensation.

Dimensions of Colors

 Hue –  Hue refers to the name of the colors. By using the term hue we distinguish one color from the other. It is the quality which separates colors from each other. It is the contrast between redness, blueness and greenness. For eg. red, blue, green, yellow, these are the name of colors which separates them from the rest. 

Value –Value refers to the lightness or darkness of the colors. When color is mixed with white forms tints or light shades. When mixed with black it form dark shades of that particular hue. The hues are located somewhere in between the extremes of the white and black in value scale. Every hue or a color wheel has its own vale level known as normal or home value. For example when white is added in blue (hue) it will form the tint of blue or sky blue shade. When black is added to the same hue it will form dark blue or navy blue.

 Intensity / chroma –intensity refers to the purity and impurity of a hue. It is the difference between a strong colour and weak colour. The more pure a hue will be the more intensity it may contain. It is sometimes known as chroma. It is the brightness or dullness of a hue. Bright colours have high and dull colours have low intensity.

Properties of colors and theory

  1.  Prang Colour Theory

       In prang color theory there are 12 colours in the colour wheel.

Color wheel – Color wheel are logical combination of colors on it. The purpose of the it is to create an aesthetic feeling of style and appeal.

 Primary colours –Primary colours are equal distance apart on the color wheel. They are “primary” as no color combination can create such colors.

 Secondary colours – Colors halfway between the primary colors. Created by mixing two primary colors together. Orange, green, violet or purple.

Tertiary colours – These are hues intermediary between primary and secondary hues. Created by mixing one primary with one secondary colors. Red – orange, yellow – orange, blue – green, yellow – green, blue – violet and red – violet.

  1. Mansell Colours Theory –

             It was created by Albert H. Munsell. According to Mansell colour theory there are total 10 fundamental colors which are divided into 2 parts.5 colour principles and 5 intermediate colours.

     5 colour  principle or the main colours are –1. Red          2. Yellow        3.    Blue     4. Green     5. Violet.

    5 intermediate colours are –  1. Red – yellow     2. Blue – green   3. Violet – red    4. Blue – violet    5. Yellow – green.

      This theory is based on the dimensions of colours i.e; hue, value and chroma or intensity.

 Color Scheme –

Monochromatic color scheme –

                    Mono means one and one pure must be the key tone of the harmonious color scheme. Monochromatic scheme is the easiest to design as well as most comfortable because it compose of like colors. The key success to this scheme is to use enough contrast through hue and intensity to make it attractive. This scheme is restful to the eye.

 Analogous color scheme –

                   Colors that are next to each other on the wheel frequently provide the basis of very pleasing combinations. Blue, blue-violet and violet has enjoyed tremendous scheme. Analogous colour schemes are often found in nature and are harmonious and pleasing to the eye. Yellow, yellow-green and green with different values and intensities of adjacent colours will make analogous colour scheme.

Complementary colour scheme –

                                   Colours that are opposite to each other on the colour wheel are considered to be complementary colours. For e.g, red and green. High contrast of complementary colour scheme creates a vibrant look particularly when used at full saturation. Therefore, scheme must be managed so it not jarring.

  • Split complementary colour scheme –

              The split complementary colour scheme is the variation of complementary colour scheme. In this addition to the base colour, it uses the two analogous colours adjacent to its complement. This colour scheme has the same strong visual contrast as the complementary colour scheme but has less tension. It makes an arrow “Y”on the colour wheel. For example – orange, green and blue-violet. It is also known as compound harmony.

Double complementary colour scheme –

                                             Superimposing a narrow ‘X’ on the colour wheel we get the two sets of complementary colours to work with. Four colours might be confusing in a small area, but they promote variety in colours. It is therefore known as tetrad colour scheme.

 Triad colour scheme

 A triangle is placed on the colour wheel will give three colours that form the triad. The primary colours like red, yellow and blue.

Psychological effects of color –

                 Colors profoundly affect our mood and temperament. A fact that a sensitive designer use to impair the mood of the garment and the wearer. A considerable literature has evolved on the psychology and symbolism of color. Some work claim to assess personality traits according to color preference, other analyse color symbolism in terms of behaviour. For example, in many western cultures white is the bridal color symbolising purity and innocence. While in India the proper bridal color is red. Likewise in Western use black for mourning ,whereas, some cultures use white. Colors convey strong emotional meaning to an audience . These are the extra Properties of colors.

 Color Psychology: White

  • purity
  • innocence
  • cleanliness
  • sense of space
  • neutrality
  • mourning (in some cultures/societies)

Color Psychology: The Color Black

  • authority
  • power
  • strength
  • evil
  • intelligence
  • thinning / slimming
  • death or mourning

Color Psychology: The Color Gray

  • neutral
  • timeless
  • practical

Color Psychology: The Color Red

  • love
  • romance
  • gentle
  • warmth
  • comfort
  • energy
  • excitement
  • intensity
  • life
  • blood

Color Psychology: Orange

  • happy
  • energetic
  • excitement
  • enthusiasm
  • warmth
  • wealth prosperity
  • sophistication
  • change
  • stimulation

Color Psychology: Yellow

  • happiness
  • laughter
  • cheery
  • warmth
  • optimism
  • hunger
  • intensity
  • frustration
  • anger
  • attention-getting

Color Psychology: Green

  • natural
  • cool
  • growth
  • money
  • health
  • envy
  • tranquility
  • harmony
  • calmness
  • fertility

Psychology of Blue

  • calmness
  • serenity
  • cold
  • uncaring
  • wisdom
  • loyalty
  • truth
  • focused
  • unappetizing

Psychology of Purple

  • royalty
  • wealth
  • sophistication
  • wisdom
  • exotic
  • spiritual
  • prosperity
  • respect
  • mystery

Psychology of Brown

  • reliability
  • stability
  • friendship
  • sadness
  • warmth
  • comfort
  • security
  • natural
  • organic
  • mourning (in some cultures/societies)

Psychology of Pink

  • romance
  • love
  • gentle
  • calming
  • Agitation

reference click


Texture means the surface quality of an object- how it looks, feels and performs. Texture describes the surface or tactile quality of a material, its degree of smoothness or roughness. The word texture describes the nature of the surface. The word ‘texture’ comes from the latin word meaning to weave. In fashion designing texture refers to the surface of fabrics or trimmings used in the garments. It is the most important element of design because people first get attract by the colour of the garment then automatically reach out to the texture whether they will feel comfortable or not. Texture is also define as a visual and tangible structure of a surface or substance. Texture appeals to not just one, but three of our senses ; touch, sight and hearing. Texture affects the look of a garment, the feel, influence the appearance of the person wearing the garment. Texture , basically connected to the weave of the fabric.

Factors affecting texture in textile

All the fabric textures, from the purest chiffon to the bulkiest fleece to the solid canvas, depend on variations of only four factors :-

Fibre content –

Fibre content is the generic or family name like, wool, nylon, rayon, polyester etc.. They are the substance from which the yarn and fabrics are made. The length, chemical composition, shape and performance are characteristics of a fibre which greatly influence the final texture. Natural fibres such as – cotton, wool, silk etc; man-made fibres and synthetic fibres such as rayon, nylon, polyester, acetate, olefin etc. Long filament fibres such as silk and synthetics give shinier, smoother and cooler touch and sometimes stronger fabrics. Short staple fibres such as cotton, wool etc, give relatively duller, rougher, fuzzier and warmer touch and sometimes weaker fabrics. Some fibres or combination of fibres contributes to static electricity which results in clinging garments. Functional qualities such as- resiliency or elasticity, absorbency, heat conductivity, shrinkage control, resistance to fire, insects acids, alkalies etc all depends upon the fibre.

Yarn structure –

Yarn is the intermediary state between fibres and fabrics. Fibres have spun into yarn in the next step of making fabrics. The fibres have spun and twisted in either ‘S’ or ‘Z’ direction to form a yarn. The amount of yarn twisted influence the surface and hand. High twisted yarns contribute to hard-surface, smooth, strong and somewhat elastic fabrics. The soft-surfaced yarns results from the low-twisted yarns. The direction of the twist is also important ‘S’ or ‘Z’ twist. The number of strand a yarn has twisted together influences the textural thickness and strength. Generally, the higher the strands, the stronger the yarn is. The thickness of the yarn influences how many strands can be used and consequently the fineness or coarseness of a texture. Novelty yarns create interesting surface. Elastic and high bulky yarns introduce other tactile effects and performance.

Fabric structure –

Fabric structure is the way fibrous yarns are interlock into a flat fabric. Varieties in fabric structure provide the most dramatic most easily seen difference in the texture. The structure cause by film, felt, or made of various fibres bond directly to each other without first being spun, it could be net, lace, braid, knit or woven. Weaving generally gives the strongest and most stable fabric structure.

Grains –

The direction of the yarn, also called grain, both woven and non-woven fabrics have grain. Woven fabrics or grain,with lengthwise and crosswise yarns straight, and interwoven at right angles, lace,net and felt lack this flexibility of grain, but hold crisps shapes better. Grain is critical to shaping and draping effects.

Combination of fabric structure –

          These create new textural potential but need caution. If two fibres are bonded or laminated together, they produce a thicker, stronger texture but their joining must be permanent on grain and their care and performance quality is compatible. They rarely serve well in garments destined for stress and strain.

Finishes –

          Chemical or mechanical finishes which use heat, pressure and/or chemicals may either affect the fabric surface or penetrate the fibre. Some finishes are primary for appearance, such as bleaching, embossing, flocking, glazing etc. Some finishes affect both visual and tactile qualities  such as singering, napping, shearing, puckering and seizing. With their advantages, finishes may also create undesired side effects which the industry constantly strives to reduce.

What words describe texture ?

 Loopy, fuzzy, furry, soft, shiny, dull, bulky, rough, crip,smooth and sheer.

Why texture is important in fashion ?

 It can increase or decrease the body size, it can draw added attention to a design.

Sometimes we can add texture to the fabric by adding stitched details, pin tucks and embellishments as well. While choosing texture do give in the tests – tactile and visual, some texture can only be felt, but commonly textures can be distinguish visually. Not all textures that are visually appealing can be worn. To wear or drape attires you have to be alert about the feel of the texture – if you are not comfortable wearing a certain texture.


Forms is defined as a 3- dimensional area enclosed by a surface. If the form is hollow we often perceive the interior as volume, if it is solid, the interior is described as mass. Forms may be created using a combination of two or more shapes. Shapes and forms as visual design elements are fascinating and challenging because they are so malleable. It is a 3-D element of design and has length, width and height. Form is volume and enclosed by a surface, we are remained. They have power to evoke feelings similar to those of line

 It adds another dimension to shape. A circle is a flat two-dimensional shape. When you add the shading that transforms the circle into a sphere it takes on three-dimensional form like a ball you could throw or bounce.Basic forms are three-dimensional figures including spheres, cubes, cylinders, pyramids and cones. If an object has height, width and depth it is a form.

 A form is negative or positive. A brick-shaped indentation in a wall is a negative form while an exposed brick is a positive form. Form can also be static or dynamic. Static means still, so a ball resting on the table is static. A dynamic form suggests motion such as a ball flying across the room.


 Equal forms

  • It include sphere and cube.

Unequal forms

  •  It include cone, cylinder, bell, pyramid, cuboid, dome, barrel, hour glass etc.

For more info about the form you can comment below or simply react out to me via mail. Or for more content you can just ping me. I hope you enjoyed this blogs.