Explore topic-wise InterviewSolutions in Current Affairs.

a. Neutral point.

b. 400 V in between two phases. 230 V in between a phase and neutral. 

c. B4 glows because it is connected between the lines phase and neutral B, and B2 glows with low brightness. Each bulb gets 200 V as it is connected in series with 400 V.

d. Three phases in a transformer have separate fuses. So power supply problem in a line need not affect the other phases.

Mechanical energy → Electrical energy

• Idukki – Moolamattom.
• Idukki – Pallivasal.
• Alappuzha – Kayamkulam.

• Water from dam. 
• Nuclear energy. 
• Heat produced during the combustion of Naphta, Coal, Lignite

 ….etc

Possible. If split-ring commutator is used in a generator instead of slip rings, we will get DC.

1. Same direction.

2. No.

3. No. emf increases and decreases.

From coal, naphtha, water from dam, exciters and big batteries. Field magnets are used as electromagnets. Mechanical energy also obtained from heat released by nuclear fusion.

1. Direction of AB is downward.

2. Direction of CD is upward.

3. from D to A.

4. from B1 to B2.

a. P = V_p × I_p

500 W = V_p × 1A, V_p = 500 V

b. I_s = \( \left(\cfrac { I_p × V_p }{ V_s }\right)\) = \(\cfrac{1 \times 500}{100}\) = 5A

c. Primary and secondary powers are equal

\(\cfrac{Secondary\,power}{Primary\,power}\) = 1

The number of turns 6f a secondary coil of a step-down transformer compared to primary will be increase.

Vibrates corresponding to the sound signals.

1. Whenever there is a change in the magnetic flux linked with a coil, an emf is induced in the coil.

2. Whenever there is a relative motion between the magnet and the solenoid, there is flow of electricity.

3. Number of turns increased. Strong Magnet used Magnet / Solenoid moves with greater speed.

Electric energy is lost in the form of heat.

1. Second circuit

2. Back emf more

3. On both circuits

4. On second circuit

5. When AC passes through a solenoid, a changing magnetic field is generated around it. Due to this, an induced emf is generated inside the solenoid. This induced emf is in a direction opposite to that applied on the coil. Hence this is a back emf. This back emf reduces the effective voltage in the circuit.

Inductors are used in the electronic circuits, to control and decrease current without power loss.

Moving coil galvanometer: Voice coil

Correct option is D) smooth

c. Turbine is rotated to operate the generator.

e. Electricity is produced at 11 kV.

d. Transmission of electricity from the Power Station starts at 220 kV.

b. Voltage is reduced from 220 kV to 66 \ kV to supply electricity to large scale industries.

a. Distribution transformer reduces the voltage from 11 kV to 230 V.

f. Domestic consumers get electricity.

a. To reduce energy loss in the form of heat high voltage is used for long-distance transmission. 

b. Transmission through populated areas is difficult. Transmission lines must be at a great height to ensure safety.

c. To reduce high transmission line voltage as and when required. Step down transformers are used for this purpose.

1. Watt-hour meter.

2. From the main switch.

3. Watthour meter.

4. The electricity used is measured using a Watthour meter.

5. Phase line.

6. The electricity reaches the electrical appliances through the main switch. Therefore instead of turning each switch OFF, the main switch can be switched OFF. The main switch is placed just after the Watthour meter.

7. Earth line.

• Phase – Red.
• Neutral – Black.
• Earth – Green.

8. Pin E.

9. Parallel.

AB will be near the south pole of the magnet and CD will be near the north pole.

100 times direction of current change in the circuit.

1. Vapour pressure of a liquid is the pressure exerted by the vapour which is in equilibrium with liquid at a given temperature. 

2. Boiling point of a liquid is the temperature at which the vapour pressure of liquid becomes equal to the atmospheric pressure. Thus, lower the vapour pressure of a liquid higher will be its boiling point and vice-versa. 

3. At high altitudes atmospheric pressure is low. Therefore, liquids at high altitudes boil at lower temperatures in comparison to that at sea level. In a pressure cooker, the internal pressure is greater than atmospheric pressure. Hence, in a pressure cooker water boils at a temperature higher than its normal boiling point of 100 °C. Thus, cooking becomes more effective.

1. PV = nRT 

2. XN₂ = \(\frac{nN_2}{nN_2+no_2}\) = \(\frac{0.2}{0.8}\) = 0.25

Xo₂ = 1 - 0.25 = 0.75

pN₂ = XN₂ x P_Total = 0.25 x1.8 atm = 0.45 atm

po₂ = Xo₂ x P_Total = 0.75 x1.8 atm = 1.35 atm

3. It is the temperature at which a real gas obeys ideal gas law over an appreciable range of pressure.

(a) Graph (A).

(b) \(\frac{p_1V_1}{T_1}\) = \(\frac{p_2V_2}{T_2}\) 

(c) V₂ = \(\frac{p_1V_1T_2}{p_2T_1}\) 

= \(\frac{760\,mm\,of\,Hg\times700\ mL\times288.15\ K}{600\ mm\ of\ Hg\times298.15\ K} \) 

= 856.93 mL

1. It states that equal volumes of all gases under the same conditions of temperature and pressure contain equal number of molecules.

2. v ∝ n (at constant P and T) 

⇒ V = k × n where k is a proportionality constant..

3. 22.71098 L 

4. According to Avogadro law, for n moles of an ideal gas, 

V = k × n 

But n = \(\frac{m}{M}\) where m is the mass of the gas and M is its molar mass. 

Thus, V = k × \(\frac{m}{M}\) 

On rearranging the above equation, 

M = k × \(\frac{m}{V}\) = k × d 

⇒ M ∝ d

(a) It is the square root of the mean of the squares of speeds of various molecules of the gas at a given temperature.

(b)  U_rms = \(\sqrt{\frac{u_1^2+u_2^2+...+u_n^2}{n}}\)  

OR U_rms = \(\frac{\sqrt{3RT}}{M}\)  

OR U_rms = \(\sqrt{\frac{3pV}{M}}\) 

(c) (i)  U_rms = \(\sqrt{\frac{3\times8.314\,JK^{-1}mol^{-1}\times\,300K}{16\,g\,mol^{-1}}}\) 

=21.63 ms^-1

(ii) U_mp = \(\sqrt{\frac{2RT}{M}}\)

U_mp = ^{\(\sqrt{\frac{2\times8.314\,JK^{-1}mol^{-1}\times\,298K}{14\,g\,mol^{-1}}}\)} 

= 18.81 ms^-1

1. The attractive force between two temporary dipoles is known as London forces or Dispersion forces.

2. London forces are always attractive and the interaction energy is inversely proportional to the sixth power of the distance between two interacting particles.

1. Thermal energy is the energy of a body arising from motion of its atoms or molecules. The movement of particles due to thermal energy is called thermal motion.

2. At – 273.15 °C oxygen will not exist as a gas. In fact all the gases get liquified before this temperature is reached. It is the absolute zero of temperature, which is the lowest hypothetical or imaginary temperature at which gases are supposed to occupy zero volume.

The van der Waal parameter ‘a’ is a measure of the magnitude of intermolecular forces. The van der Waal parameter ‘b’ which is also called co-volume is a measure of effective size of the gas molecules.

The compressibility factor is given by the expression \(\frac{pV}{nRT}\) .

Boyle temperature or Boyle point

The Correct option is (4) Troposphere and Troposphere 

D. All the above

Joule/second.

The units on the rate of heat transfer are Joule/second, also known as a Watt.

Area.

The window has a surface area A

Correct option (1)   Due to hydrogen bonding

Explanation:

 Due to hydrogen bonding HF has Boiling amongst Hydrogen halides.

The correct option (1) Increase with pressure increase, decrease with temperature increase

Explanation:

Physical adoption increases on increasing pressure but decreases on increasing temperature.

Correct option  (4)  I, III

Explanation:

VBT does not explain the colour exhibited by co-ordination compounds.

VBT  does not explains and gives quantitative interpretation of magnetic data.

VBT does  not distinguish between weak field ligand and strong field ligand.

(d) Work function difference between the atoms of the two elements

B. First increases, then decreases 

The Correct option is D. P+F=C+2 

C. Elements should form compounds with each other

(c) Hume-Rothery rule

Correct option (4) (I) and (III) only

Explanation:

(1) VBT does not explain colour exhibited by complex of transition metal. 

(2) VBT does not distinguish between strong and weak complex. 

(3) VBT does not give quantitative interpretation of magnetic properties. 

∴ Ascending to question statement I and III are correct