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The instrument used to measure the specific gravity is called Hydrometer

Isolator is a disconnecting switch which is not having the making and breaking capacity. 

Bus coupler - 2000A 

Feeders - 1600 A

This device is used during the installation of a motor to determine the direction of the motor once it is installed. The shaft is mechanically rotated in the desired direction and the meter indicates if that is the direction in which the motor will rotate. 

Phase sequence indicator used to indicate the 3-phase direction- comes in two styles; Lights and meters. In the lighted variety, a sequence of light goes on for the phase sequence being read, while the meter indicates which phase direction it is reading.  

Infrared or thermal scanners are used to measure temperature without contact with the equipment. They produce an image of the component showing temperature variations, this is effective in spotting worn or loose connections and components in industrial circuits.  

Parts of the battery are 

a. Battery container. 

b. Battery cover. 

c. Positive plate (Pb o₂). 

d. Negative plate (Pb). 

e. Cell connector. 

f. Grid. 

g. Cell separator (porous material). 

h. Sediment chamber. 

i. Positive and negative terminals. 

j. Vent plugs.

k. Dilutes sulphuric acid (electrolyte). 

Always battery capacity is expressed in Ampere – hour.

While preparing electrolyte for lead acid battery sulphuric acid is added to distilled water. 

As in secondary cell distance between two plates is greater and their sizes are big. There is no polarization in secondary cell. Due to these cause internal resistance of secondary cell is low. 

Efficiencey of secondary cell is measured in ampere-hour.

Basic principles of ED are, 

a) All the contacts of corresponding relays and contactors are shown in de-energised condition. 

b) Control circuit gives us idea about ON / OFF selection of motor, fuse rating, forward reverse control, seal in protections etc. 

c) Power circuits are drawn in thick lines and control circuits are drawn in thin lines. 

d) When relay or contactor energises normally open contact closes and normally closed contact opens. 

e) Auxillary contacts acts with main device such as contactors and relay. 

Start push button should be connected in parallel and stop push button in series in the circuit. 

Special current limiting resistance is connected in series with the seal in contact

Negative side of the DC supply to avoid galvanic effect on the coil, which will corrode the coil.  

The operating voltage of 3C is 48V DC.

When a breaker is closed on fault condition there will be continuous tripping and closing of the breaker because 3C is energized. Anti pumping in circuit avoids frequent tripping and closing of circuit breaker when the breaker is closed in fault condition. 

Correct Answer is: (a) Y but not in X 

Correct Answer is: (b) 4

Correct Answer is: (c) -6.8 eV 

The total energy in the first excited state is - 13.6/4 eV = -3.4 eV.

This consists of the kinetic energy of 3.4 eV and the potential energy of -6.8 eV. In order to take the PE here as zero, we add 6.8 eV to all energy levels. The total energy in the ground state then becomes (- 13.6 + 6.8) eV = - 6.8 eV.

Correct Answer is: (c) l/2√3

Correct Answer is: (a)

The Carius halogen method in analytical chemistry is a method for the quantitative determination of halogens in chemical substances. A known mass of an organic compound is heated with fuming nitric acid in the presence of silver nitrate contained in a hard glass tube known as carius tube, in a furnace.

(a) Mixture of acetone and water. It can be separated by distillation.

(b) Mixture of petrol and kerosene. Can be separated by distillation.

(c) Mixture of oil and water. Can be separated by fractional distillation.

(d) Mixture of naphthalene and ammonium chloride. Separating naphthalene by filtration and then separation of ammonium chloride from water by evaporation.

(e) Mixture of pigments from a flower petal extract. Can be separated by chromatography.

Benzene is a non polar compound and non-polar solide dissolve in non-polar solvent, and polar so solution dissolve in polar solvent. It means as the polarity of solvent increases the solubility of non-polar solute decreases.

The order of polarity of toluene, bromo benzene and potassium Hydroxide is

Potassium Hydroxide > bromobenzene > tolulene

therefore, the order of solubility of benzene  will be---

tolune > bromo benzene > potassium Hydroxide.

(a) Vapour pressure decreases due to increase in volume. 

(b) Rate of evaporation remains same and rate of condensation decreases. 

(c) Finally the same vapour pressure is restored and the rate of evaporation becomes equal to the rate.

1. pH is a logarithmic scale used to express the hydronium ion concenration in molarity more conveniently. The pH of a solution is defined as negative logarithm to the base 10 of the activity of hydrogen ion.

pH = — log a_H+ = —log[H⁺]

2. [H⁺] = 3.8 × 10^-3 

pH = -log[H⁺]

= -log [3.8 × 10^-3] = -(-2.42) = 2.42

pH = -log[H⁺]

=-log(3.8 x10^-3)

= 2.42

pH= -log[H⁺] = 3.76 

log[H⁺] = – 3.76 

[H⁺] = antilog of (- 3.76) 

= 1.738 × 10^-4 mol L^-1

The relation between ionization constant of an acid and that of its conjugate base is K_a 

x K_b= K_w

K_a x K_b = K_w 

∴ K_b = \(\frac{K_w}{K_a}\)

The conjugate base of HF is F^- , 

∴ K_b(F^-) = \(\frac{K_w}{K_{a(HF)}}\) = \(\frac{1\times10^{-14}}{6.8\times10^{-4}}\) = 1.5 x 10^-11

The conjugate base of HCOOH is HCOO^-.

∴ K_b(HCOO^-) = \(\frac{K_w}{K_{a(HCOOH)}}\) =  \(\frac{1\times10^{-14}}{1.8\times10^{-4}}\)  = 5.6 x 10^-11 

The conjugate base of HCN is CN^-.

∴ K_b(CN-) = \(\frac{K_w}{K_{a(HCN)}}\)  = \(\frac{1\times10^{-14}}{4.8\times10^{-9}}\) = 2.1 x 10^-9 

H= -log [H⁺] 

or log [H⁺] = -3.76 = -4.24 

 [H⁺] = antilog (-3.76) = 1.74 × 10^-4 M

K_sp = 2.3 x 10^-5

[SO₄^-] = 1.8 x 10^-2

Ag₂SO₄ \(\rightleftharpoons\) 2Ag⁺ + SO₄^-2

K_sp = [Ag⁺]²[SO₄^-2] 

\(\therefore\) [Ag⁺]² = \(\frac{K_{sp}}{[SO_4^{-2}]}\)

[Ag⁺]² = \(\frac{2.3\times10^{-5}}{1.8\times10^{-2}}\)

 = 1.28 x 10^-3

or [Ag⁺]² = 12.8 x 10^-4

[Ag⁺] = \(\sqrt{12.8\times10^{-4}}\) 

 = 3.58 x 10^-2 M

or [Ag⁺] = 0.0358 M

In magnetic dipole Force ∝1/r⁴  

In the given question, Force ∝x⁻ⁿ   

Hence, n = 4

Correct answer is option (b) : [Momentum] =  [MLT^–1]

[Planck's constant] = [ML²T^–1]

Momentum and Planck's constant do not have same dimensions.