Doubtly
@Doubtly · Joined Feb 2021
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- [Algebra] Maharashtra Board Maths part 1 previous year paper march 2020 Maharashtra Board Maths previous year paper march 2020 To view online View To download for offline study download link For study now 1
- If α, β and γ are three consecutive terms of a non-constant G.P. such that the equations Correct option is 4) βγ α x² + 2β x + γ = 0 Let β = α t, γ = α t² therefore α x² + 2α tx + α t² = 0 ⇒ x² + 2tx + t² = 0 ⇒ (x + t)² = 0 ⇒ x =... 1
- The Boolean expression ∼(p⇒(∼q)) is equivalent to : Correct option is A) p^q Explaination:: ∼(p⇒(∼q)) as p⇒q \ is \ same \ as \ ∼p v q we get ∼((∼p) v(∼q)) = p^q 1
- A triangle has a vertex at (1, 2) and the mid points of the two sides through it are (-1, 1) and (2, 3). Then the centroid of this triangle is: Correct option is 2) ( 1/3,rm 2 ) Explanation:: 1
- A plane which bisects the angle between the two given planes 2x – y + 2z – 4 = 0 and x + 2y + 2z – 2 = 0, passes through the point :0 Correct option is (4) (2, –4, 1) Explaination:: From question, the equations of planes given are: 2x – y + 2z – 4 = 0 X + 2y + 2z – 2 = 0 Th... 1
- The equation of the common tangent to the curves y^2 = 16x and xy = - 4 is Answer: (a) x - y + 4 = 0 Any tangent to the parabola y² = 16x (here 4a = 16 , so a = 4 ) with slope m is y = mx + 4/m For it to touch the h... 1
- The equation of the common tangent to the curves y^2 = 8x and xy = - 1 is Correct option is (d) y=x+2 Explaination:: tangents to the curve y²=8x is y=mx+2/m , so it must satisfy xy=-1 x(mx+2/m)=-1 mx²+2/mx+1=0 , si... 1
- The general solution of the differential equation (y^2 – x^3 )dx – xydy = 0 (x ≠ 0) is : The correct option is 2) y²+2x³+cx²=0 Detailed explaination 1
- Let a ∈ (0,π/2) be fixed. If the integral ∫ tan x + tan α/tan x - tan α dx = A(x) cos 2α + B(x) sin 2α + C, where C is a Correct option is (4) x – α and log_e|sin(x – α)| Detailed Explaination: ∫ tan x + tan α/tan x - tan α dx = ∫ sin x /cos x+ sin α/cos α/sin... 1
- A coil of inductance 300 mH and resistance 2 is connected to a source of voltage 2 V. Correct answer is option d) 0.1 s Explaination: During growth of charge in an inductance, I = I₀ (1 – e ^(–Rt/L)) or I₀/2 = I₀(1 – e^( –Rt/L... 1
- When current in a coil changes from 5 A to 2 A in 0.1 s, an average voltage of 50 V is produced Correct option is 2) 1.67H Explaination EMF = L × di/dt 50 = L × (5-2)/0.1 = L × 30 L = 5/3 = 1.67 1
- A rectangular loop is present in the magnetic field region of an infinite long wire. Now the loop is being rotated as shown in the figure. option B is correct 1
- A conducting square loop is placed in a magnetic field B with its plane perpendicular to the field. The sides of the loop start shrinking at a constant rate Correct solution is option A ) 2aα B Explaination: "a" at any time "t" , the side of the square a= (a₀-α_t) , where α₀ side at t=0 . at this... 1
- A conducting circular loop made of a thin wire, has area 3.5 x 10–3 m2 and resistance 10Ω . Correct option is A) 0.14 mC Explaination: Q=triangleφ/R=1/10A(B_f-B_i) \\ =1/10×3.5×10⁻³(0.4sinπ/2-0) \\ 1/10×3.5×10⁻³(0.4-0)\\ 1.4×10⁻⁴=0.... 1
- Suppose that f is differentiable for all x and that f’(x) ≤ 2 for all x. If f(1) = 2 and f(4) = 8, then f(2) has the value equal to LMV Theorem for f in [1, 2] forall c in(1, 2) f(2)-f(1)/2-1 =f'(c) ≤ 2 f(2)-f(1) ≤ 2 ⇒ f(2) ≤ 4 ...(1) Again, using LMV Theorem in [2, 4] fo... 1
- When seen from below, the blades of a ceiling fan are seen to be revolving anticlockwise and their speed is decreasing. Correct answer is (B) Angular velocity downwards, angular acceleration upwards. 1
- The system of linear equations x + y + z = 2 , 2x + 3y + 2z = 5 , 2x + 3y + (a2 – 1)z = a + 1 Correct option is inconsistent when |a|= sqrt3 Solution:: D=beginvmatrix 1&1&1\\2&3&2\\ 2 &3 &a²-1 endvmatrix D= 1(3a²-3-6) - 1(2a²-2-4) + 1... 1
- O. Why do we see bands separating in column chromatography? we see bands separating in column chromatography Because , In column chromatography, the solutes get adsorbed on the stationary phase, they... 1