RRB JE CE (CBT II) Mock Test- 2

Döbereiner showed that when the three elements were written in the order of increasing atomic masses, the atomic mass of the middle element was roughly the average of the atomic masses of the other two elements.

Application:

Atomic mass of Na = avg. mass (Li , K)

= 7 + 39 / 2 = 23a.m.u

Other example of Döbereiner triads are:

Therefore, number of links = 20/0.2 = 100

When the concrete is in contact with or buried under aggressive subsoil/groundwater, this condition is considered very severe.

∴ For a curved beam loaded with point load, at any section x-x

There will be an action of Shear Force, Bending Moment, and Torsional Moment as shown in the figure.

The physical properties include strength, weight, thickness or size, etc. Chemical properties specify mainly the composition of the chemical content of the product and precautionary measures required to store the products.

It does not include workmanship to be achieved during construction.

LSF = Percentage of lime/Percentage of alumina + iron oxide + silica

It generally lies between 0.66 to 1.02.

These are supposed to carry the following loads due to moving crane:

1) vertical loads or (gravity load)

2) lateral loads (produced due to jerk experienced while loading, unloading, and movement of the cranes)

3) longitudinal loads (produced due to longitudinal movement of the crane)

∴ Gantry girders are designed to resist lateral, longitudinal, and vertical loads.

Grade compensation on B.G. is equal to 0.04 percent per degree of curve,

Compensation allowed = 0/04 × 4 = 0.16 per cent.

Now, gradient of curve is 1:200 i.e. 0.5 per cent.

∴ Actual Gradient = 0.50 – 0.16 = 0.34 per cent or 1:294

Important Point:

Grade compensation for different tracks on curves

• Stopping sight distance (SSD) or the absolute minimum sight distance

• Intermediate sight distance (ISD) is defined as twice SSD

• Overtaking sight distance (OSD) for safe overtaking operation

• Headlight sight distance is the distance visible to a driver during night driving under the illumination of headlights

• Safe sight distance to enter into an intersection

The table below shows a comparison between all different types of excavating equipment.

Damp Proof Coarse:- D.P.C. shall be 2.5 cm thick cement concrete 1 : 1.5 : 3, mixed with one kg of impermo per bag of cement or other standard waterproofing materials as specified and painted with two coats of bitumen.

Roof:- Roofs shall be of R.C.C slab with an insulation layer and lime concrete terracing above, supported over R.S joists or R.C.C beams as required. The height of rooms shall not be less than 3.7 m.

Flooring:- Mosaic flooring must be provided, including staircase. Floors of bedrooms shall be colored and polished of 2.5 cm cement concrete over 7.5 cm lime concrete. Floors of others shall be of 2.5 cm cement concrete over 7.5 cm lime concrete polished.

Finishing:- Inside and outside finishing shall be of 12 mm cement lime plastered 1 : 1 : 6 Drawing, dining, and bedrooms inside shall be distempered, and others inside whitewashed 3 coats.

Important Specifications:

Foundation and Plinth:- Foundation and plinth shall be of first-class brickwork in lime mortar or 1 : 6 cement mortar over lime concrete or 1 : 4 : 8 cement concrete.

Superstructure:- Superstructure shall be of first-class with lime mortar or 1 : 6 cement mortar. lintels over doors and windows shall be of R.C.C.

∴ Weight of wooden block = Weight of the volume of fluid displaced

Let,

The density of wooden block = γ_b, the density of water = γ_w, and volume of block = V

Weight of wooden block = γ_b × V

Weight of the volume of fluid displaced = γ_w × 2/3 × V

∴ γ_b = 2/3 × γ_w

∴ The relative density for the wooden block is 2/3.

• Using an optically readable medium, data is recorded by making marks in a pattern that can be read back with the help of light.

• CD-ROM and DVD are optically readable media

• Floppy disk is a type of disk storage composed of a disk of thin and flexible magnetic storage medium.

• A hard disk is an electromechanical data storage device that uses magnetic storage to store and retrieve digital information.

• Magnetic tape is a medium for magnetic recording, made of a thin, long, narrow strip of plastic film which has a magnetic coating.

• The Supply curve is a graphical representation that shows the relationship between the quantity of product that a seller is able and willing to supply and the product’s price.

• The quantity of the product supplied is on the horizontal axis (X-Axis), and the product price is measured on the vertical axis (Y-Axis) of the graph.

• Time is an important factor to supply since suppliers must react quickly to a change in demand or price.

Contour Surface: An imaginary at which every point is located at the same elevation above the datum is known as contour surface.

Contour Interval: The difference in elevation between successive contour lines on a given map is fixed. This vertical distance between any two contour lines on a map is called the contour interval.

Contour Gradient: An imaginary line on the surface of the earth having a constant inclination with the horizontal (slope) is called contour gradient. It is expressed as the ratio of the vertical height to a specified horizontal distance.

Important Point:

Horizontal Equivalent: The horizontal distance between two points on two consecutive contour lines for a given slope is known as horizontal equivalent. depends upon the slope of the ground and required grade for construction of a road, canal and contour interval.

∴ Maximum area of steel = 0.04 × 250 × 200 = 2000 mm²

Important Point:

The minimum area of steel required for a section is given by

• Elevated levels of nitrogen dioxide can cause damage to the human respiratory tract and increase a person's vulnerability to, and the severity of, respiratory infections and asthma.

• Long-term exposure to high levels of nitrogen dioxide can cause chronic lung disease (acute bronchitis)

• High levels of nitrogen dioxide are also harmful to vegetation—decreasing growth or reducing crop yields.

• It may also affect the senses, for example, by reducing a person's ability to smell an odour.

Tips & Tricks:

Important Point:

For more shortcuts and tricks, you can refer .

1. Arithmetic Logic Unit (ALU): It performs all the arithmetic operations like addition (+), multiplication (*), subtraction (-), division (/) on the numerical data directed by the control unit. All the logical operations, like less than (<), greater="" than="" (="">), equal to (ALU also carries out =), not equal to (≠) etc..
2. Control Unit (CU): It controls and coordinates all the operations taking place in the system. It controls the flow of data and information from one unit to the other.

3. Registers/Memory Unit (MU): To execute a program, data and instructions need to be stored temporarily. This storage is done in the MU. The data and instructions are retrieved from MU by Control Unit to supply ALU as required by the program.

   

i) Lesser energy requirement

ii) lower nutrient requirement

iii) production of biogas which is a valuable source of energy

Anaerobic Decomposition:

Organic Impurities + Anaerobic Bacteria → CO₂ + CH₄ + Energy

i) Addition polymerization: It is a type of reaction that involves the simple linking of the monomers without forming any by-products. E.g., PVC, polyethylene, etc.

ii) Condensation polymerization: It is a type of reaction in which the linking of monomers involves the loss of small molecules like water as by-products. E.g., polyurethane, polyacetals, etc.

iii) Co-polymerization: It is the addition polymerization of two or more different monomers. E.g., Vinyl chloroacetate, Butadiene-styrene co-polymers, etc.

Bernoulli’s equation: This equation related to the conservation of energy of the fluid mass and it is applicable only for ideal fluid flow.

Hagen-Poiseuille equation: This equation computes head loss due to the friction in laminar as well as turbulent flow. It cannot help analyzing the viscous fluid motion.

Navier – Stokes equation: This equation considers pressure force, gravity force and viscous force and hence it completely analyses the viscous fluid motion.

However, it does not holds good for turbulent flow. Thus, Reynold’s equation is used to analyze turbulent flow.

The different type of hammers used for pile driving are:

i) Drop hammer

ii) Single actin hammer

iii) Double acting hammer

iv) Differential acting hammer

v) Hydraulic hammer

vi) Diesel hammer

vii) Vibrating hammer

viii) Sonic hammer

Important Point:

A heavy hammer with a small drop is more effective than a small hammer with a large drop.

The modular ratio m has the value of 280/3σ_cbc, where σ_cbc is the permissible compressive stress in concrete due to bending in N/mm².

1. scaling of cement concrete

2. shrinkage crack

3. spalling of Joints

4. Wrapping cracks

5. Mud Pumping

6. Structural cracks

Flexible Pavement failures: -

1. Alligator (map) cracking

2. Consolidation of pavement layer

3. Shear failure

4. Longitudinal Cracking

5. Frost Heaving

6. Reflection cracking

7. Lack of binding to the lower course

8. Formation of waves and corruption.

You should also know this:

Frost Heaving:

Frost heaving is often misunderstood for shear or other types of failures. In shear failure, the upheaval of a portion of pavement is followed with a depression. In the case of frost heaving, there is mostly a localized heaving-up pavement portion depending upon the groundwater and climatic conditions.

Mud Pumping:

Mud pumping recognized when the soil slurry ejects out through the joints and cracks of cement concrete pavement caused during the downward movement of ​the slab under the heavy wheel loads. Pumping is noticed just after the rains in cement concrete pavements that are placed on clayey soil subgrade.

q_ultimate = 1.3 c N_c + γDN_q + 0.4 γBN_γ

q_net=1.3cN_c+γD(N_q−1)+0.4γBN_γ

N_c = 9.6, N_q = 2.7 and N_γ = 1.2

q_net=1.3cN_c+γD(N_q−1)+0.4γBNγq_net = 1634.49 kN/m²

∴q_net ≈ 1634.50 kN/m²

When both ends are hinged for a given compression, effective length is equal to the actual length of the member.

Tips & Tricks:

For providing an Indian type W.C. the R.C.C slab in the toilet portion should be sunk by 50 cm.

Loamy Soil contains almost equal proportion od sand silt and clay and is found along the beds of river. Since it is most suitable for agriculture, it is also one of the alluvial soil.

Peat is an organic soil having fibrous aggregates of macroscopic and microscopic particles. It is formed from vegetal matter under excessive moisture.

Important Points:

Caliche contains gravel, silt, and sand, and its particles are cemented by calcium carbonate.

Tuff is composed of very fine particles ejected from volcanoes during its explosion and is deposited by wind or water.

Advantages of a flat-footed rail are as followed:

i) No chair is required as rails are directly spiked to the sleepers.

ii) It is stiffer vertically as well as laterally.

iii) It is less liable to kinks development.

iv) It is economical than all other types of rail.

v) It distributes the load over a larger area of the sleeper.

where

e = void ratio

D = effective size of soil particle

γ = weight density of fluid

μ = viscosity of fluid

c = constant (depends upon the shape of the particle)

∴ The coefficient of permeability depends upon the shape of particles, the diameter of particles, and void ratio.

• When a file is deleted, the data is not initially removed from the hard disk.

• Instead, the space on the disk that was occupied by the deleted data is "deallocated."

• After it is deallocated, space is available for use when new data is written to the disk.

• Until space is overwritten, it is possible to recover the deleted data by using a low-level disk editor or data-recovery software

Nitrogen and oxygen are two major gases of the atmosphere. Carbon dioxide (CO2), Helium, Ozone, Argon and hydrogen are found in lesser quantities. Apart from these gases, tiny dust particles are also present in the air.

The atmospheric composition of gases are as follow

CO + Blood → Carboxyhemoglobin

Important Point:

• Carbon monoxide is a toxic gas, but it is difficult for people to detect

• Carbon monoxide is a product of incomplete combustion of organic matter

• It is often produced by motor vehicles that run on gasoline, diesel, or other carbon-based fuels

• Exposure at 100 ppm or greater can be dangerous to the human heart.

It is quite large (23 million square km in 1992 and 28.3 million square km in 2000). A small ozone hole also occurs over the North Pole, it was discovered in 1990.

• Nalanda Mahavihara was founded in the 5th century CE by Kumargupta I of the Gupta Dynasty.

• It was an ancient Mahavihara, a Buddhist monastery.

• Sri Gupta founded the Gupta Empire.

• Chandragupta, I was the first great ruler of the Gupta Empire, who assumed the title of Maharajadhiraja.

• Samudragupta was the 2nd ruler of the Gupta Empire. He was also called Napoleon of India.

• Under the 69^th amendment of the Indian Constitution, Special status was given to Delhi as the National Capital Territory of Delhi.

• Under the 86^th amendment of the Indian Constitution, Elementary education was made a fundamental right under article 21 A.

• Under the 44^th amendment of the Indian Constitution, the Right to Property was deleted as of a fundamental right.

• Under the 42^nd amendment of the Indian Constitution, Preamble was amended for the first time.

• World Brain Day is observed on July 22 every year.

• The day aims at promoting the interest of neurology. Previously, World Brain Day has covered topics like dementia, epilepsy, and stroke, in cooperation with other societies.

• World Brain Day 2019 theme is Migraine: The Painful Truth.

• This year, the focus is on migraine, which is known to be one of the world's most common brain diseases.

1/f = 1/v - 1/u

Where,

f= focal length =−20cm

v= image⁡ distance=v

u= Object distance = -40 cm

1/-20 = 1/v - (1/-40)

V = -13.33 cm

The reaction of Zn and HCl is example of displacement reaction.

When a more reactive element displaces a less reactive element from its compound then that is known as displacement reaction. Both metals and nonmetals take part in displacement reactions

Application:

The underlying reaction between hydrochloric acid and granulated zinc is :

Zn + 2HCl → ZnCl₂ + H₂

From the above reaction the gas released is H₂

H₂ is colourless odourless gas which burns with a popping sound.

By storage of rainwater, not only availability of water in increased but fall in water level can also be prevented.

Thus, the book value of property gradually reduces at a constant amount year after year up to the limit of scrap value.

Based on alignment, tunnels are classified as follows:

i) Off-spur tunnels: These are short length tunnels to negotiate minor local obstacles, which cannot be avoided by permitted curves.

ii) Saddle or base tunnels: These tunnels are constructed along the natural slopes till the slopes do not exceed the ruling gradient.

iii) Slope tunnels: These tunnels are constructed in steep hills for economic and safe operations of roads and railways.

iv) Spiral tunnels: These tunnels are provided in narrow valleys in the form of loops in the interior of the mountain so as to increase the length of the tunnel to avoid steep slopes.

i) Reaction Turbine: A turbine for which both pressure energy and kinetic energy is available at the inlet is a reaction turbine.

E.g. Francis Turbine, Kaplan Turbine and Propeller Turbine.

They are useful for low head and high discharge.

ii) Impulse Turbine: A turbine for which only kinetic energy is available at the inlet is an impulse turbine.

E.g., Pelton Turbine and Turgo Impulse Turbine.

They are useful for high head and low discharge.

Where M = multiplying constantly.

N = No of revolution passes the zero mark [ + ve for clockwise and –ve for anti-clockwise revolution]

C = Constant of index arm = 0; when the anchor point is outside the plan

A=100×[8.378−1.378+10×1+0]

= 1700cm²

The cross-sectional area of the plate through various sections.

Let the width of the plate be ‘b’, the thickness of plate ‘t’ and diameter of the hole be ‘dh’

For section 1-1: A_section 1-1 = (b – 3 d_h) × t

For section 2-2: A_section 2-2 = (b – 2 d_h) × t

For section 3-3: A_section 3-3 = (b – 1 d_h) × t

∴ Critical section for the cover plate is section 1-1 as the cross-sectional area is least.

Critical section for Main Plate:

For main plate, although the cross-sectional area is minimum at section 1-1 maximum force is resisted at section 3-3 as force is first experienced at section 3-3 and the remaining is then transferred to section 2-2 and section 1-1 respectively.

The dept of sealant should not be more than one half of the width of the joint and should not be less than 4 mm in any case.

Centroid: The point that may be considered as the center of a one– or two–dimensional figure i.e., the sum of the displacements of all points in the figure from such a point being zero.

For the circle, the centroid lies at the centre.

∴ The centroid of the circle lies at the centre.

E.g., Rural building, temples, low rise flats, tenements, residential bungalows, etc.

Framed structure: It comprises of slabs resting on beams that are supported by a network of columns.

E.g.,.,project’s cost andneeded Multistoried or High-rise buildings.

Composite structure: It is structured with a combination of load bearing as well as framed structure.

E.g. Warehouses, halls, large factory sheds, workshops, etc.

Important Points:

Sills: They are provided between the bottom of the window frame and above the top of the walls below.

Weather shed/Chajja: These are generally combined with the lintels to protect doors, windows or ventilators from sun, rain, wind, frost, etc.

• Windows explorer has become a very powerful utility for navigation and searching directories for files of the system

• Windows Explorer is the file management tool that comes with Windows

• It gives the ability to rename, copy, move or delete the folders and files on the computer's drives

• Folders and files are displayed hierarchically within Windows Explorer

• Folders contain subfolders as well as files

• Windows Explorer is called File Explorer in Window 10

• The Fourth Anglo Mysore war was fought between the Mysore Kingdom and The East India Company in 1799.

• Tipu Sultan was killed in the battle.

• The First Anglo Mysore war was fought between Hyder Ali and The East India Company in 1767.

• The Second Anglo Mysore war was fought between Hyder Ali and The East India Company in 1782.

• The Third Anglo Mysore war was fought between Tipu Sultan and The East India Company in 1791.

LHS = 2

RHS = 3

LCM (2,3) = 6

Multiply Oxygen on LHS by 3 and on RHS by 2

a Fe + 3 O₂ + → 2 Fe₂O₃

Balancing Fe:

RHS = 4

LHS = 1

Multiply Fe on LHS by 4

4 Fe + 3 O₂ + → 2 Fe₂O₃

Saturated Hydrocarbon:

Compounds of carbon, which are linked by only single bonds between the carbon atoms are called saturated compounds.

Unsaturated Hydrocarbon:

Compounds of carbon having double or triple bonds between their carbon atoms are called unsaturated compounds.

Application:

Saturated hydrocarbons give a clean flame while unsaturated carbon compounds will give a yellow flame with lots of black smoke.

In a balanced section, an increase in the area of steel will result in higher tensile stress carrying capacity.

To counteract or generate equivalent compressive stress/force, the neutral axis has to come down.

In a singly reinforced rectangular beam section,

implies that

x_u∝A_st

which means as the percentage area of tensile steel increases the depth of the neutral axis increases

Imhoff tank: It is a robust and effective settler that causes a suspended solids reduction of 50 to 70%, COD reduction of 25 to 50%, and leads to potentially good sludge stabilization.

It consists of two compartments:

Upper Compartment: This compartment has a circular or rectangular shape with V-shaped walls and a slot at the bottom, allowing solids to settle into the digestion compartment, while preventing foul gas from rising up and disturbing the settling process. It is exposed to atmosphere, and thus working condition is aerobic.

Lower Compartment: In this compartment, sludge accumulates and is compacted and partially stabilized through anaerobic digestion. Thus, working condition is anaerobic

On awarding the contract, 5% of the contract value is included as ​the contingency in the cost plan.

I­­p = w­­­­l­ - w­p

I­p = 20%

w­l = 40%

20% = 40% - w­p

wL = 20%

(ii) Diagonal scale: It can measure three successive dimensions. (unit, 1/10unit, 1/10 unit) e.g. (m, dm, cm)

(iii) Vernier Scale: It is a device for measuring accurately the fractional part of the smallest division on a graduated scale.

(iv) Graphical Scale: It is a line drawn on the map representing the corresponding ground distance.

Hence, Diagonal scale is used to measure three dimensions on a scale.

They are classified as:

a) Shallow or fixed plate bearings – suitable for spans up to 12 m.

b) Deep cast base bearings – suitable for spans 12 m to 20 m.

c) Rocker bearings – suitable for spans more than 20 m.

d) Sliding plate bearings – suitable for girders of span 12 or 20 m.

S=q_u/q_r

q_u = unconfined compressive strength of soil in an undisturbed state

q_r = unconfined compressive strength of soil in the remolded state

Classification of soil based on Sensitivity:

Hence option B is the right answer.

Check Valve: These valves are used to check the flow of water in reverse direction. These are generally provided on the delivery side of the pump. These valves work automatically.

Scour valve: This valve is used to drain the water out of the pipe system.

Steps to derive UH:

a) A hydrograph plotted by rainfall excess of a given duration (D-h) is selected.

b) Base flow is separated from the selected hydrograph to derive DRH.

c) The area under the DRH is calculated, which will be equal to the runoff volume.

d) The runoff volume is then divided by the catchment area to obtain effective rainfall.

e) The ordinates of the DRH are divided by the effective rainfall (Obtained from step “d”) to get the ordinates of UH of D-hr duration.

∴ The ordinates of unit hydrograph can be obtained by dividing each of the ordinates of direct runoff by the depth of direct runoff.

Where L is the length of span in meters,

hence impact factor will decrease on increase with span.

For such structure, loads from the slab roof or trusses and floors are transmitted through walls to the firm soil below the ground. In load-bearing structures, the wall thickness of the upper floors is lesser than the lower floor. Therefore, the carpet area of higher level is more than the lower level.

Such type of structure is most suited for buildings up to three storeys and a where hard strata of soil is available. It is generally adopted for residential bungalow, tenement, temples, rural buildings, etc.

δl=P×L/A×E

Where

δl = deformation of a bar

L = Length of a bar

A = cross-sectional area of bar

E = Modulus of Elasticity of section

Calculation:

Given: L = 2000 mm, E = 2.1 × 10⁵ N/mm² and P = 10⁵ N

It is also called as a tree system, it consists of one main supply line, from which originates (generally at right angles) a number of sub main pipes. Each sub main is then divided into several branch pipes, called laterals. This type of distribution system is suitable for older towns which have developed in a haphazard manner, without properly planned road e.g. old city, irregularly grown city, etc.

It is easier to construct as no designing or planning is required. The pressure at the ends becomes undesirably low and it is difficult to maintain chlorine levels at the ends.

• The internet is a globally connected network system that transmits data via various types of media. Sometimes it is referred to as a ‘network of networks’

• The World Wide Web, or simply web, is a way of accessing information over the medium of the internet

• A web browser is a software application for accessing information on the World Wide Web

• The Battle of Ghaghra was fought between Sultan Muhammad Lodhi (The last claimant of the Lodhi Empire) and Babur (Founder of Mughal Empire in India) in 1529.

• Muhammad Lodhi was defeated by Babur in this battle.

• The Battle of Ghaghra was the decisive battle for the Mughals in India as It led to the complete control of the Mughals in North India.

KE gained = mgh

KE gained = 8*10*20

KE gained = 1600 J

KE = (1/2)mv2

1600 = (1/2)*8*v²

Solve for v

V = Square root of 400

V = 20 m/s²

Maximum limit of concrete are as follows:

Components of Diversion head work are as follows:

1) Weir or Barrage

2) Divide wall

3) Fish ladder

4) Approach channel or pocket

5) Scouring sluices

6) Silt Excluder

7) Head regulator

8) Guide bank or marginal bund

∴ “Pocket” is a part of Diversion Head Work.

These are used for lining furnace, ovens, etc.

As the molecules of dissolved metals and salts are large compared to the water molecules, water squeezes through the membrane leaving the metals and salts behind.

Colloidal Solids: These are extremely small size (1-200 mill microns) particles. These do not settle out on standing and cannot be removed by conventional physical treatment processes.

Colloids exhibit Brownian movement and are generally electrically charged with respect to their surroundings and hence Coagulation is the best treatment to be provided.

Volatile Solids: These are removed by sludge digestion technique as they are very fine particles. They undergo aerobic/anaerobic reactions for decomposition and forms sludge at the bottom of the tank.

Settleable Solids: They are removed by sedimentation.

A. Using cross staffs

There are three types of cross-staff

1. Open cross-staff

2. The French cross-staff and

3. The Adjustable cross-staff

B. Using optical Square

C. Using Prism square

D. Using Steel tape

Hence, line ranger is not used for measuring perpendicular offsets

1) Flow is steady

2) Fluid is incompressible

3) Fluid is non-viscous (inviscid)

4) Equation is applicable along a streamline

5) Effect of friction is neglected

6) Only pressure and gravity forces are taken into account

7) Velocity is uniform over the cross-section

Hauling equipment are classified as:

i) Dump Trucks

a) Side or rear dump trucks

b) Bottom dump trucks

ii) Dumpers

∴ l = unsupported length of column and d = lateral dimension of the column

• In May 2017, WannaCry ransomware targeted computers running the Microsoft Windows operating system by encrypting data and demanding ransom payments in the Bitcoin cryptocurrency

• Around 37 incidents of ransomware attacks were reported to the Indian Computer Emergency Response Team (CERT-In), according to Minister of State for Electronics and IT

Adware is any software application in which advertising banners are displayed while a program is running

Spyware is mostly used for the purposes of tracking and storing internet user movements on the web and provides pop-up ads to the internet user

Trojan horse is a program that appears harmless but in fact malicious which misleads user of its true intent

Range ⇒R=u²sin⁡2α/g

Calculation:

Let u and a be velocity of projection and the angle of projection.

Then Maximum height reached ⇒H=u2sin²⁡α/2g

Range ⇒R=u²sin⁡2α/g

Given that R = 3 x H

FIGURE FROM

1) Pitch → Inner most central portion.

2) Heart wood → The inner annual rings surrounding the pith.

3) Sap wood → The outer annual rings between Heart wood and cambium layer

4) Cambium layer → A thin layer of sap between sap wood and inner bark

5) Inner bark → It gives protection of the cambium layer.

6) Outer bark → It is the outermost part of the tree.

For 20 m chain length,

The degree of curve (D) is given by ⇒ D=1146/R

For 30 m chain length,

Degree of curve (D) is given by ⇒ D=1729/R

Calculation:

∴ For 20 m chain length, D = 1146/229.2 = 5°

∴ For 30 m chain length, D = 1729/229.2 = 7.54°

∴ Most appropriate option is 5° and hence 20 m chain length should be considered.

We are aware that normally rainwater has a pH of 5.6. When the pH of the rainwater drops below 5.6, it is called acid rain.

Acid rain refers to the ways in which acid from the atmosphere is deposited on the earth’s surface. Oxides of nitrogen and sulphur, which are acidic in nature, can be blown by the wind along with solid particles in the atmosphere and finally settle down either on the ground as dry deposition or in water, fog and snow as wet deposition.

Acid rain is a byproduct of a variety of human activities that emit the oxides of sulphur and nitrogen in the atmosphere. As mentioned earlier, the burning of fossil fuels (which contain sulphur and nitrogenous matter) such as coal and oil in power stations and furnaces or petrol and diesel in motor engines produce sulphur dioxide and nitrogen oxides.

SO₂ and NO₂ after oxidation and reaction with water are major contributors to acid rain because polluted air usually contains particulate matter that catalyzes the oxidation.

2SO₂ (g) + O₂ (g) + 2H₂O (l) → 2H₂SO₄ (aq)

4NO₂ (g) + O₂ (g)+ 2H₂O (l) → 4HNO₃ (aq)

The bad effects of acid rain

• When acid rain falls and flows as groundwater reaches rivers, lakes, etc., it affects plants and animal life in the aquatic ecosystem.

• Acid rain is harmful to agriculture, trees, and plants as it dissolves and washes away nutrients needed for their growth.

• It causes respiratory ailments in human beings and animal

• It may also cause corrosion in many buildings bridges, monuments, fencing, etc

• It irritates the eyes and skin of human beings

• This rain reduces the lustre of the metals too

• Acid rain damages buildings and other structures made of stone or metal

• The Taj Mahal in India has been affected by acid rain

• River Sutlej originates outside India, at Mount Kailash, Tibet.

• It enters India through Shipki la Pass.

• Yamuna River originates at Yamunotri Glacier, Uttarakhand.

• Ganga River originates at Gaumukh, Gangotri Glacier, Uttarakhand.

• Luni is the only river that flows in Rajasthan.

Esterification reaction:

Esters are formed by the reaction of an acid and an alcohol.

Ethanoic acid reacts with absolute ethanol in the presence of an acid catalyst to give an ester.

Esters are sweet-smelling substances. These are used in making perfumes and as flavouring agents

Reaction:

CH₃ – COOH + CH₃ CH₂ COOH → CH₃ – CO – O – CH₂ – CH₃

Here e_x, e_y, and e_z are the strain in the x, y, and z directions, respectively.

Some pigments are toxic, such as those used in lead paint. Paint manufacturers replaced lead white with a less toxic substitute, which can even be used to colour food titanium white (titanium dioxide).

Its purpose is to gather water draining from higher sloping ground before it reaches the flat land.

Side drains: These drains are also provided parallel to the roadway for plain region.

Sloping drains: These are provided at the intersections of the roadways and also along the short paths.

Cross drains: These are provided along the cross drainage portion of the roadway.