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Statement-1 :- sky waves are not used in the transmission of T.V signals

Statement-2 :- T.V signals have a frequency range of 100 to 200 MHz

(a) Statement-1 is true, statement-2 is true.Statement-2 is a correct explanation for statement-1. (b) Statement-1 is true, statement-2 is true,... View Article

To transmit 1 Khz frequency signal, wave length of the signal should be ___________m

1) 3 x 103 2) 3 x 105 3) 3 x 107 4) 3 x 1010 Answer: 2) 3 x 105... View Article

Electromagnetic waves with frequencies greater than the critical frequency of ionosphere cannot be used for communication using sky wave propagation, because

1) the refractive index of the ionosphere becomes very high for f > fc 2) the refractive index of the... View Article

A G.P. consists of an even number of terms. If the sum of all the terms is 5 times the sum of terms occupying odd places, then the common ratio is

(a) 5 (b) 1 (c) 4 (d) 3 Solution: Let the G.P be a, ar, ar2 … S = a... View Article

a, b, c are in G.P. with 1 < a < b < n, and n > 1 is an integer. log_a n, log_b n, log_c n form a sequence. This sequence is which one of the following?

(a) Harmonic progression (b) Arithmetic progression (c) Geometric progression (d) None of these Solution: Given that a, b, c are... View Article

The value of the infinite product 6^1/2 ×6^1/4× 6^1/8×6^1/16×…is

(a) 6 (b) 36 (c) 216 (d) ∞ Solution: 61/2 ×61/4× 61/8×61/16×… = 6(1/2 + 1/4 + 1/8 + 1/16... View Article

Let S_n (1 ≤ n ≤ 9) denotes the sum of n terms of series 1 + 22 + 333 + ……………..+ 9999999999, then for 2 ≤ n ≤ 9

(a) Sn – Sn-1 = (1/9)(10n – n2 + n) (b) Sn = (1/9)(10n – n2 + 2n – 2)... View Article

Given that α, γ are the roots of the equation Ax² – 4x + 1 = 0, and β, δ the roots of the equation Bx² – 6x + 1 = 0, the values of A and B such that α, β, γ, and δ are in H. P. are

(a) A = 3, B = 8 (b) A = – 3, B = 8 (c) A = 3, B... View Article

If (1 – P) (1 + 3x + 9x² + 27x³ + 81x⁴ + 243x⁵) = 1 – P⁶, P ≠ 1, then find the value of P/x is

(a) 1/3 (b) 3 (c) 1/2 (d) 2 Solution: (1 – P) (1 + 3x + 9x2 + 27x3 +... View Article

What is the greatest value of the positive integer n satisfying the condition 1 + ½ + ¼ + ⅛ + …..+ 1/2^n-1< 2 – 1/1000?

(a) 8 (b) 9 (c) 10 (d) 11 Solution: Given 1 + ½ + ¼ + ⅛ + …..+ 1/2n-1<... View Article

If a = 1 + (√3-1) + (√3-1)² + (√3-1)³ + …. and ab = 1, then a and b are the roots of the equation

(a) x2 + 4x – 1 = 0 (b) x2 – 4x – 1 = 0 (c) x2 + 4x... View Article

If a, b, c are positive numbers, then least value of (a + b + c)(1/a + 1/b + 1/c) is

(a) 1 (b) 6 (c) 9 (d) None Solution: We use A.M ≥ H.M (a+b+c)/3 ≥ 3/[(1/a) + (1/b) +... View Article

Consider the sequence 8A + 2B, 6A + B, 4A, 2A – B, ……., Which term of this sequence will have a coefficient of A which is twice the coefficient of B?

(a) 10th (b) 14th (c) 16th (d) None of these Solution: Given sequence 8A + 2B, 6A + B, 4A,... View Article

ABC is a right angled triangle in which ∠B = 90⁰ and BC = a. If n points L₁, L₂, …, L_n on AB are such that AB is divided in n + 1 equal parts and L₁M₁, L₂M₂,…, L_nM_n are line segments parallel to BC and M₁, M₂,…., M_n are on AC, then the sum of the lengths of L₁M₁, L₂M₂,…., L_nM_n is

(a) a(n+1)/2 (b) a(n-1)/2 (c) an/2 (d) none of these Solution: AL1/AB = L1M1/BC 1/(n+1) = L1M1/a =>L1M1 = a/(n+1)... View Article

If |r|>1 and x = a + (a/r) + (a/r²) + … to ∞, y = b – (b/r) + (b/r²) – …to ∞ and z = c + (c/r²) + (c/r⁴) + …∞ then xy/z =

(a) ab/c (b) ac/b (c) bc/a (d) 1 Solution: Sum of infinite GP, S = a/(1-r) where a is the... View Article

Let A_n be the sum of the first n terms of the geometric series 704 + (704/2) + (704/4) + (704/8) + … and B_n be the sum of the first n terms of the geometric series 1984 – (1984/2) + (1984/4) – (1984/8) + …If A_n = B_n, then the value of n is (where n ∈ N).

(a) 4 (b) 5 (c) 6 (d) 7 Solution: We know sum of n terms of G.P = a(1 –... View Article

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