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The advantages of secondary cells over primary cell are.

a. It gives high current capacity. 

b. Its internal resistance is very low. 

c. It gives a constant current. 

d. It posses very high efficiency. 

e. It posses fairly constant emf. 

f. It posses good mechanical strength. 

g. It posses large storage capacity

h. It can be renewed by charging after it is discharged. 

i. It is durable. 

Polarization:

The hydrogen bubbles which are clinging over the surface of copper electrode (anode) becomes a thin film of hydrogen over the copper electrode. This hydrogen film increases the internal resistance and reduces the emf of the cell and hence the cell soon becomes inactive. This effect is known as polarization.

Local action:

In voltaic cell it is observed that, when the cell is not connected to the load and not supplying any current zinc will continuously dissolving in the electrolyte. This is due to the impurities (copper, iron, tin, and lead) in the commercial zinc. So that whenever commercial zinc is used as a electrode, separate small cells are developed between the impurities and zinc with the presence of electrolyte. These local cells consume always zinc and the emf developed by those local cells are always opposite to the main emf. The action of these cells is known as local action. 

Primary cells are those cells, which cannot be re-charged after the substances (electrolyte, electrode and container) used in it becomes useless. 

The common primary cells in use are, 

a. Simple voltaic cell (one fluid cell). 

b. Daniel cell (two fluid cell). 

c. Leclanche cell (two fluid cell). 

d. Dry cell. 

e. Standard cell or Weston cadmium cell.

Secondary cells are those cells, which can be re-charged and use again once they discharged or used for the work for number of times with out re-newing it’s materials. 

Most commonly used secondary cells are, 

a. Lead acid cell. 

b. Nickel iron alkaline cell. 

c. Nickel cadmium alkaline cell. 

The classifications of cell are given below.

a. Primary cells. 

b. Secondary cells. 

a. Low voltage: Voltage not exceeding 250V. That is 0 – 250V. 

b. Medium voltage: Voltage above 250V upto 650V comes under medium voltage. 

c. High voltage: Voltage above 650V upto 33 kV comes under high voltage. 

d. Extra high voltage: Above 33 kV voltages are extra high voltages. 

The classifications of DC motor.

a. DC series motor. 

b. DC shunt motor. 

c. DC compound motor. 

There are two types of DC compound motor. 

a. Differential compound motor. 

b. Commulative compound motor. 

Answer is (iii) 2L

Let P is the observation point at a distance r from -2q and at (L+r) from +8q. 

Given Now, Net EFI at P = 0

∴ \(\overrightarrow{E_1}\) = EFI (Electric Field Intensity) at P due to +8q

\(\overrightarrow{E_2}\) = EFI (Electric Field Intensity) at P due to -2q

\(|\overrightarrow{E_1|}=|\overrightarrow{E_2}|\)

∴ \(\frac{K(8q)}{(L+r)^2}=\frac{1}{(r)^2}\)

∴ \(\frac{4}{(L+r)^2}=\frac{1}{(r)^2}\)

4r2 = (L+r)2

2r = L+r

r = L

∴ P is at x = L + L = 2L from origin

The factory outlets offer discounts ranging between 25% - 75% all the year round. 

Factory Outlet- deals in surplus stock , Directly sold by the manufacturer at a discount. Stock can be either first-quality merchandise or discontinued, irregular, cancelled orders at a very low price. The discount can range from 25-75%.

(A+B)×(A-B)

=(A+B)×A-(A×B)×B

=(A×A)+(B×A)-(A×B)-(B×B)

BCZ[A×(B−C)=A×B−A×C]

=(B×A)+(B×A)[BCZ A×A=0,A×B=-(B×A)]

=2(B×A)

ANSWER

Correct option (4) they are chemically reactive

Explanation:

Intustitial compound are – 

 (i) hard 

 (ii) chemically inert 

 (iv) high m.p. As interstitial compounds are chamically inert

Correct option (1) [Fe(phen)₃] ²⁺  

Explanation:

In the complexes of Fe²⁺, CO²⁺, Ni²⁺ upon oxidation, complexes of Fe³⁺, CO²⁺ & Ni³⁺ stabilizes whereas in case of removing 3^rd electron from Zn becomes difficult.

The correct option is (3) Synthesis of ammonia from N₂ and H₂.

Explanation:

where Δn_g > O

The correct option (4) 100 ppm

Explanation:

Moles of CaSO₄ = 10^–3 moles 

Mass of water = 1000g 

DOH (in terms of CaCO₃) = (10^-3 x 100)/1000 x 10⁶ = 100ppm

Correct answer is 9

Coordination no. = 6 

Oxidation state = 3 

6 + 3 = 9

(D) It results from reaction of unsaturated hydrocarbons.

Photo chemical smog results from the action of sunlight on unsaturated hydro carbons and nitrogen oxide

(B) decrease in HOMO-LUMO gap down the group 

(C) decrease in π*-σ* gap down the group 

Highest occupied molecular orbital (HOMO) ⇒ π* 

Lowest unoccupied molecular orbital (LUMO) ⇒ σ* 

On descending the group gap between π* and σ* decreases.

Correct option (4) Both are stable 

Explanation:

Both Li₂⁺ and Li₂^-  has 0.5 bond order and hence both are stable

Correct option (3) N^3– , O^2– , F^– and Na⁺ 

Explanation:

In this we have to choose isoelectronic set of ions 

Isoelectronic species are those which have same no. of electron in total. 

So option 3 : is correct.

Correct option (3) Friedel Craft's alkylation

Explanation:

Polysubstitution is a major drawback of Friedal –Craft alkylation 

–CH₃ gp in highly activating group 

 due to +H effect of its  

Correct option is (1) ML^-1T^-1

Pt = Ft/A = change in momentum/Area

MLT^-1/L² = ML^-1T^-1

Correct option is (1) -π/2

v = dx/dt = πcosπ(t+ 1/3)

v at t = 1 = πcosπ(1+ 1/3)

= πcos(π + π/3)

= -πcos π/3

= -π/2

Correct option (2) Propanal as substrate and methanol in excess

Explanation:

Ketones < Aldehydes →Rate of NAR 

Only aldehydes are responsible for the function of acetals.

Correct option (4) (I), (II) and (III) only

Explanation:

B₂O₃ is acrolic in nature Al₂O₃ and Ca₂O₃ are amphoteric oxides of In and Tl are basic in nature.

Correct option (3) CO

Explanation:

CO is diamagnetic in nature

Correct option  (1)  CO

Explanation:

According to MOT, O₂, B₂ & NO are paramagnetic, only CO is diamagentic.

Correct option: (2) D < A < B < C

The axis of the earth is tilted at an angle of 66 \(\frac{1}2º \)  from the orbital plane and 23 \(\frac{1}2º \)  from the vertical plane. The earth maintains this tilt throughout its revolution. This is known as parallelism of the earth’s axis.

Since the parallelism of the earth’s axis is maintained same throughout the revolution, the position of the sun in relation to the earth varies apparently between Tropic of Cancer and Tropic of Capricorn. This is known as the apparent movement of the sun.

The movement of the sun is in between 23 \(\frac{1}2º \) N and 23 \(\frac{1}2º \) S.

The tilt of the earth 23 1/2° 

• At vertical plane, tilt of the earth’s axis is 23 \(\frac{1}2º \)
• At horizontal plane, the tilt is 66°.

Fingerlings are larvae of  Fish.

Correct option: (2) Muscular dystrophy

Explanation: 

Progressive degeneration of skeletal muscle mostly due to genetic disorder is muscular dystrophy where as tetany is muscular spasm due to low calcium in body fluid. Myasthenia gravis is an anto immume disorder leading to paralysis of skeletal muscles. Botulism is rare and dangerous type of food poisoning caused by bacterium Clostridium Botulinum.

Correct option (C) Meat

Correct option is B) cut back

Correct option is A) pig out

1. He said that he would do it then.

2. He says that honesty is the best policy.

3. Ramesh says that he has written a letter.

4. She said that Mahesh would be reading a book.

5. She inquired where his father was.

6. He requested me to take my book

7. The Principal ordered the peon to let that boy go out.

8. He prayed that I might live long.

9. She bade goodbye to her friends.

10. The student regretted that he had wasted his time the previous year.

Correct option is living

The number of hypervariable region in L chain is 3.