Question Discussion & Solution

Given ten digit number is 6438123953

First half of the digits are : 64381

These are rearranged in descending order, so it becomes, 86431

Second half of the digits are : 23953

These are rearranged in ascending order, so it becomes, 23359

The new number is 8643123359

Comparing the new number with the given number

We see that, 4 digits position (highlighted) remains unchanged

Hence ‘4’ is the correct answer.

The relation is:

1) Sports : Ground → Sports are organised in ground.

2) Rubber : Eraser → Rubber is used to erase writings on paper.

3) Cinema : Screen → Cinema is shown on screen

4) Drama : Stage → Drama is played on stage.

Hence, Rubber : Eraser is the correct answer.

Concept:

• The laws dealing with ideal gases naturally called ideal gas laws, and the laws determined in the seventeenth century by Boyle's observational work and in the eighteenth century by Charles.
• The Boyles Law states that the gas pressure is inversely proportional to the gas volume for a given mass of gas stored at a constant temperature.
• Charles Law states that the gas volume is directly proportional to the gas temperature for a given fixed mass of gas stored at a constant pressure. 
• An ideal gas is a gas that follows the equation:

PV = nRT at all temperatures and pressure, where P = Pressure of the ideal gas. V = Volume of the ideal gas n = Amount of ideal gas measured in terms of moles 

R = Universal gas constant T = Temperature

Mole Concept -

•  The quantity one mole of a substance signifies 6.022 × 1023 number of particles of that substance which may be atoms, molecules, or ions.
• The quantity is a universal constant like Dozen, Gross, etc., and is known as Avogadro number, denoted by NA. after the scientist Amedeo Avogadro.
• Examples- In one mole of H2, there are 6.022 × 1023 molecules of hydrogen, and the number of atoms is 2 × 6.022 × 1023, as one molecule of hydrogen contains two-atom each.
• The mass of one mole of a substance is called its Molar Mass (M) or Atomic mass expressed in grams.
• The volume occupied by a mole of gas is 22.4 L at NTP, called its Molar Volume.
• The no. of moles (n) is calculated as =

The number of particles / Avogadro’s number.

To summarise, we can say, 

Calculation:

• The molar mass of 1 mole of H₂SO₄ is =

2 × 1 + 32 + 4 × 16 = 98g

• The molar mass of 1 mole of Silver, Ag is its molecular mass 108g.
• The molar mass of CO₂ is = 12 + 2× 16 = 44g.
• 44g of CO₂ means one mole.
• 1 mole of Oxygen weighs 16 + 16 = 32g.
• Hence, the highest mass is of 1 mole of Ag.

The correct answer is Article 167.

• Article 167 of the Indian Constitution defines the duties of the Chief Minister.
• It has specified in the second schedule.
• A chief minister is understood to be "first among equals".

A Chief Minister must be:

• Chief Minister must be a citizen of India.
• Chief Minister should be a member of the state legislature.
• If a person is elected chief minister who is not a member of the legislature, then he/she must take permission from the governor.
• Chief Minister must be 25 years of age or more.

The correct answer is 8 minutes.

• It takes 8 minutes to reach the earth.

Key Points

• Light is a form of energy which is propagated as electromagnetic waves.
• In the spectrum of electromagnetic waves, it lies between the ultra-violet and infra-red region and has a wavelength between 3900 Å to 7800 Å.
• light behaves as wave and particle both. 
• Speed of light is maximum in vacuum and air (3×10⁸ m/s).
• It is a transverse wave.
• It takes 8 min 19 s to reach on the earth from the sun.
• The light reflected from the moon takes 1.28 s  to reach earth.

Additional Information

• Electromagnetic waves are transverse, hence light is a transverse wave.
• Wave nature of light explains rectilinear propagation, reflection, refraction, interference, diffraction and polarization of light. 
• Refractive Index of a medium is defined as the ratio of the speed of light in a vacuum to the speed of light in the medium. 
• Light is measured with two main alternative sets of units: radiometry consists of measurements of light power at all wavelengths, while photometry measures light with a wavelength.