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Properties of Diamagnetic substance

1. There are no atomic dipoles in diamagnetic materials because the resultant magnetic moment of each atom is zero due to paired electrons. 

2. Diamagnetic materials are repelled by a magnet. 

3. The substances are weakly repelled by the field so in a nonuniform field, these substances have a tendency to move from a strong to a weak part of the external magnetic field.

A semiconductor is a physical substance that is designed to manage and control the flow of current in electronic devices and equipment. It neither allows a freely flowing electric current nor repels it completely. 

A semiconductor is in between a conductor and insulator and commonly used in the development of electronic chips, computing components and devices. It is generally created using silicon, germanium or other pure elements.

When current flows through a conductor, heat energy is generated in the conductor. The heating effect of an electric current depends on three factors:

• The resistance, R of the conductor. A higher resistance produces more heat.
• The time, t for which current flows. The longer the time the larger the amount of heat produced
• The amount of current, I. the higher the current the larger the amount of heat generated.

Hence the heating effect produced by an electric current, I through a conductor of resistance, R for a time, t is given by H = I²Rt. This equation is called the Joule’s equation of electrical heating.

Electromagnetic waves or EM waves are waves that are created as a result of vibrations between an electric field and a magnetic field. In other words, EM waves are composed of oscillating magnetic and electric fields.

There are 6 letters in the word MONDAY. So, the total number of words is equal to the number of arrangements of these letters taken four at a time. 

The number of such arrangements = ⁶P₄ = 6/(6 - 4) = 6/2 = (6 x 5 x 4 x 3 x 2 x 1)/(2 x 1) = 360

Hence, total number of words = 360 

(ii) Total number of arrangements in this case = ⁶P₆ = 6! = 720 

(iii) Total number of arrangements when all letters are used but the first letter is a vowel 

= 2 × ⁵P₅ = 2 × 5! = 2 × 5 × 4 × 3 × 2 × 1 = 240.

Step-up transformer is used in transmission lines for transforming the high voltage produced by the alternator.The power loss of the transmission line is directly proportional to the square of the current flows through it. 

Power = I²R

The output current of the step-up transformer is less, and hence it is used for reducing the power loss. The step-up transformer is also used for starting the electrical motor, in the microwave oven, X-rays machines, etc.

x + y = 15 ⇒ y = 15 - x 

s = x² + y² ⇒ s = x² + (15 - x)² 

ds/dx = 2x + 2(15 - x) (-1) 

ds/dx = 0  2x – 30 + 2x 

0 = 4x - 30 

x = 30/4 = 7.5

d²s/dx² = 2 + 2 = 4 > 0

∴ x = 7.5 require no is y = 7.5 & x = 7.5

The space around an electric charge in which its influence can be felt is known as the electric field. 

The electric field Intensity at a point is the force experienced by a unit positive charge placed at that point. 

• Electric Field Intensity is a vector quantity. 
• t is denoted by ‘E’. 
• Electric Field = F/q. 
• Unit of E is NC^-1 or Vm^-1. 

The electric field intensity due to a positive charge is always directed away from the charge and the intensity due to a negative charge is always directed towards the charge.

Electric field intensity is the strength of an electric field at any point. It is equal to the electric force per unit charge experienced by a test charge placed at that point, or \(E= \frac{F}{q}\)

Inductive reactance is the opposition offered by the inductor in an AC circuit to the flow of ac current. 

It is represented by (X_L) and measured in ohms (Ω). Inductive reactance is mostly low for lower frequencies and high for higher frequencies. It is, however, negligible for steady DC current.

Inductive reactance X_L = ωL.

When capacitor of capacity C charged to potential V.

Then,

Electrical energy(E) = 1/2 CV².

Correct option:

(a) 2 tan^-1 x 

(b) Symmetric 

(b) perpendicular to the surface

Correct answer is (A) frequency

(d) bar(A + B) = Y

Correct answer is (A) Constant

(d) bar(A + B) = Y

(A) Converging lens

(d) both in magnetic and electric fields

(c) Pentavalent

Correct Answer is: (a) Statement-1 is True, Statement-2 is True; Statement-2 is a correct explanation for Statement-1.

Correct option is  (c) -2.2s J

Correct option is (B) (z- 1)A

Correct option is (B) 6.25 x 10¹⁸

Correct option is (B) half - life

Correct answer is (d) A rectifier

Correct Answer is:(a) Statement-1 is True, Statement-2 is True; Statement-2 is a correct explanation for Statement-1.

Correct Answer (d) Statement-1 is False, Statement-2 is True.

Correct Answer is: (d) Statement-1 is False, Statement-2 is True.

Correct Answer is: (c) 2ϕ/R 

The total charge circulating in a coil is equal to

total change in flux / total resistance

Here, reversing the magnetic field causes a change of flux by 2ϕ.

∴ Q = 2ϕ/R.

Correct Answer is: (b) T' = T

A constant force acting on a system undergoing SHM does not alter its time period. 

Correct Answer is: (b) 150R

For the first process, at constant volume,

ΔQ₁ = nC_v ΔT = C_v (-150).

For the first process, at constant pressure,

ΔQ₂ = nC_p ΔT = C_p (150).

ΔQ₁ + ΔQ₂ = (C_p -  C_v) 150 = 150R.

Correct Answer is: (b) Q/√LC 

The initial energy stored in the capacitor is Q²/2C.

When this energy gets transferred to the coil, carrying current i, 1/2 Li² = Q²/2C.

Correct Answer is: (b) λ_α > λ_β  >  λ_c

The cut-off wavelength appears when the entire energy of the incident electron gets converted to a photon. Hence, λ_c is the shortest possible wavelength. The K_β transition, from M shell to K shell, involves more energy than the K_α transition, from L shell to K shell. Hence, λ_β < λ_α.

डाइन—सेण्टीमीटर–ग्राम–सेकेण्ड में बल का मात्रक डाइन (Dyne) कहलाता है।

वसुंधरा - संज्ञा स्त्रीलिंग [संस्कृत वसुन्धरा] 

1. धरा । पृथ्वी । 

2. श्वफलक की कन्या जो सांब से ब्याही थी । 

3. एक देवी का नाम । 

4. देश । राज्य (को कहते हैं) ।

“किसी बंद लूप या परिपथ में विद्युत वाहक बल(EMF) का बीजगणितीय योग, उस परिपथ के प्रतिरोधकों के सिरों पर उत्पन्न विभवान्तरों(voltage) के बीजगणितीय योग के बराबर होता हैं।”

The impact parameter is explained as the upright distance between the route of a projectile and the centre of a potential field invented by an object that the projectile is impending.

Work done = \(\int\limits_{10}^0fdx\) = \(\int\limits_{10}^02xdx\) = \([x^2]_{10}^0\) = 0² - 10² = -100

Standard temperature & pressure(STP) conditions imply a temperature 273.15k and a pressure of 1atm. When these conditions meet, one mole of any gas occupies 22.4litres exactly.
⇒ At STP, one mole of a gas occupies 22.4litres of volume.

Electrolysis is used in Electrorefining and Electroplating

Vapour pressure is not a collegative property