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Electric current is expressed as the amount of charge flowing through a particular area in unit time. Quantitatively, electric current is defined as the rate of flow of electric charge.

Correct option: (B) NH₄Cl < NaCl < NaCN

Explanation: 

Since NH₄Cl is the salt of (WB + SA) so pH < 7, NaCl is salt of (SA + SB) so pH = 7 and NaCN is salt of (WA + SB) so pH < 7.

Answer: (B)

The power gain is highest in Common emitter: This transistor configuration is probably the most widely used. The circuit provides a medium input and output impedance levels. Both current and voltage gain can be described as medium, but the output is the inverse of the input, i.e. 180° phase change. 

In circuit a&c, both the diode are in forward bias, hence both will have same potential drop across them (symmetry)

However, in circuit b, one diode is forward bais and other is reverse, hence they both wont have same p.d. across them.

Search Results Featured snippet from the web Potassium metal crystallizes in a face-centred arrangement of atoms where the edge of the unit cell is 0.

In an atom, electrons (negatively charged) revolve around the positively charged nucleus in a definite circular path called as orbits or shells. Each orbit or shell has a fixed energy and these circular orbits are known as orbital shells.

Niels Bohr explained the line spectrum of the hydrogen atom by assuming that the electron moved in circular orbits and that orbits with only certain radii were allowed. The orbit closest to the nucleus represented the ground state of the atom and was most stable; orbits farther away were higher-energy excited states.

36.

The equation of any tangent to y2=4ax is

y=mx+ma​

If it touches x2=4ay then, the equation.

⇒x2=4a(mx+ma​) has equal roots.

⇒mx2−4am2x−4a2=0 has equal roots

If the roots are equal, the discriminant is equal to 0

i.e.,b2−4ac=0

⇒16a2m4+16a2m=0

⇒16a2m4=−16a2m

m=−1

Putting m=−1 in y=mx+am we get,

y=−x−a

⇒x+y+a=0 This is the common tangent to the two parabola.

The left ventricle of the heart pumps oxygenated blood into the aorta. From there, blood passes through major arteries, which branch into muscular arteries and then microscopic arterioles. The arterioles branch into the capillary networks that supply tissues with oxygen and nutrients.

Lyophilization is the process of preserving something by freezing it very quickly and then subjecting it to a vacuum which removes ice.

Formula to calculate the strain energy due to pure shear: U =K ∫V ² / ( 2GA ) dx limit 0 to L Where, V= Shear load G = Shear modulus or Modulus of rigidity A = Area of cross section.

\(J=\frac{I}{\pi R^2}\)

\(I'=J(\pi(\frac{R}{2})^2)\)

\(=\frac{I}{\pi R^2}\,\,\frac{\pi R^2}{4}\)

\(I'=\frac{I}{4}=\frac{1}{4}=0.25A\)

Here you haven't specified that work function of metal is in joule or ev. So to solve it we are giving you the direction:

Calculate the energy of photon E = hc/λ 
where h (planks constant) = 6.63 x 10^-34
c = 3x 10⁸ m/s
λ = wavelength in metre of photon = 26.52 x 10^-9 m

Now divide the work function (in joule)  by the energy of photon you will get the no. of photon.

Alkanes with double the number of carbon atoms

Spirulina produces high quantity of protein.

We know that when the mass is suspended, the spring stretches by l, then Mg=kl. And energy stored in spring = kl²/2 = (kl)l/2 = Mgl/2.

When the spring oscillates at the maximum displacement, additional potential energy stored = kl²/2 = Mgl/2.

Therefore maximum potential energy or total potential energy = Mgl/2+Mgl/2 = Mgl

Given,

f = 60Hz

B_m = 1.5 tesla

A = 2500 cm²

E₁ = 1200 v

E₂ = 550 v

Induced emf is equation 

\(E_1 = 4.41 \,f\,N_1\,\phi _m\)     ......(i)

\(E_2 = 4.41 \,f\,N_2\,\phi _m\)     ......(ii)

where

N₁ - number of turn in primary winding high voltage

N₂ - number of turn in secondary winding low voltage 

\(\phi_m = B_m\times A\) 

Then

\(E_1 = 4.44 \,f\,N_1\,B_m\,A\)

\(N_1 = \frac{E_1}{4.44 f B_mA}\)

\(N_1= \frac{1200}{4.44 \times60\times 1.5 \times2500\times10^{-4}}\) 

\(N_1 = \frac{1200}{99.9}\) 

N₁ = 12.01 turns

Similarly 

\(N_2= \frac{E_2}{4.44 \times60\times 1.5 \times2500\times 10^{-4}}\) 

\(N_2 = \frac{550}{99.9}\) 

N₂ = 5.50 turns

Low voltage side turn N₂ = 5.50 turns

High voltage side turn N₁ = 12.01 turns

Given equation is x⁴ - 2x³ - 3x² + 4x - 1 = 0

roots are x₁, x₂, x₃, x₄ such that x₁ < x₂ < x₃ < x₄.

x₁ x₂ + x₁x₃ + x₁x₄ + x₂x₃ + x₂x₄ + x₃x₄ = \(\frac{c}a = -3\)-----(i)

Given that the product of two roots is units.

Let x₁x₄ = 1

Also product of roots is x₁ x₂ x₃ x₄ = \(\frac{e}a=-1\)

⇒ x₂ x₃ = -1

(\(\because\) x₂ x₄ = 1 by assuming)

\(\therefore\) From (i), we get

x₁ x₂ + x₁ x₃ + 1 - 1 + x₂ x₄ + x₃ x₄ = -3

⇒ x₁ x₂ + x₁ x₃ + x₂ x₄ + x₃ x₄ = -3

Correct option is B) Neither you nor I understood what he was saying.

As we know (t₁/2) = (0.693/k)

Given, (t₁/2) = 10

∴ 10 = (0.693/k)

∴ k = (0.693/10)

= 0.0693

In fact in this condition nature of adsorption is exothermic and ΔH is negative. It means at any given temperature ΔH and TΔS is both negative but value of ΔH is oftenly more than TΔS. Change in free energy (ΔG) is also negative.

ΔG = ΔT - TΔS (ΔH > S)

(-ve)(-ve)(-ve)

It is an alloy of 95% lanthanoid and 5% iron and traces of S, C, Ca and Al. Used in lighter flint, bullet tips etc.

X = NO₂
Y = N₂O

(i) E° - cell = E° - cathode = 0.81 - (-2.36) = 3.17 V

(ii) E - cell = E°cell - (0.0591 V/2)log([Mg²⁺]/[Ag⁺])

= (3.17 V) - (0.0591 V/2)log{0.1/(0.0001)²}

= (3.17 V) - 10.2068 V = 2.9632 V

(a) 2KMnO₄→ K₂MnO₄ + MnO₂ + O₂
(b) 3K2MnO₄ → MnO^-₄ + MnO₂ + 2H₂O