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Why is tap water a good conductor of electricity?

Tap water a good conductor of electricity since it contains some impurities, i.e. small amounts of sodium, calcium and magnesium salts dissolved.... View Article

The value of solar constant is approximately

The value of solar constant is approximately 1.366 kilowatts per square meter (kW/m2) at solam minimum and approximately 0.1% greater, i.e.... View Article

Give the meaning of the term vibgyor. With which phenomenon is it connected?

The seven colours of the spectrum of white light is denoted by the term VIBGYOR.Here,V - VioletI - IndigoB - BlueG - GreenY - YellowO - OrangeR -... View Article

Do electromagnetic waves carry energy and momentum?

Yes, the electromagnetic waves carry both energy and momentum.... View Article

Why is the convex mirror called as the diverging mirror?

The convex mirror is also called the diverging mirror because this mirror diverges light when they strike its reflecting surface.... View Article

“Higher the latitude, lower the temperature” give reason.

Higher the latitude, lower the temperature. The sun’s rays hit at a flatter angle at higher latitudes, so the solar energy is spread over a... View Article

Find the centre of mass of a triangular lamina.

The centre of mass of a triangular lamina is at the intersection of the medians. Thus, it is the centroid of the triangle. The below figure shows... View Article

If one root of 5x2 + 13x + k = 0 is the reciprocal of the other root, then find the value of k.

Given quadratic equation is: 5x2 + 13x + k = 0 Let α and 1/α be the roots of given equation. Product of roots = (α) ×... View Article

What is the reciprocal of -5?

Let y be the reciprocal of -5.As we know, the product of a number and its reciprocal is equal to 1.So, (-5) × y = 1y = -1/5Therefore, the... View Article

What is the predecessor of 17?

(a) 16 (b) 18 (c) 0 (d) 17Correct option: (a) 16The predecessor of any number can be obtained by subtracting 1 from it.The predecessor of 17 = 17... View Article

The value of tan 75Â° is

(a) 2 + √3(b) 2 - √3(c) 1 + √3(d) √3 - 2Correct option: (a) 2 + √3The value of tan 75° is 2 + √3.... View Article

What is the value of period of 2 sin x cos x?

Let the given function be y = 2 sin x cos xThus, y = sin 2xWe know that the period of sin ax is 2π/a.The period of sin 2x = 2π/2 =... View Article

Find the square root of 2304 by prime factorisation method.

The prime factorisation of 2304 is:2304 = 2 x 2 x 2 x 2 x 2 x 2 x 2 x 2 x 3 x 3To find the square root, we need to group the pairs of equal... View Article

The opposite sides of a rectangle are

(a) equal(b) parallel(c) unequal(d) Both (a) and (b)Correct option: (d)The opposite sides of a rectangle are equal and parallel.... View Article

Prove that (tan A + sin A)/(tan A – sin A) = (sec A + 1)/(sec A – 1).

LHS = (tan A + sin A)/(tan A - sin A) = [(sin A/cos A) + sin A]/ [(sin A/cos A) - sin A] = [sin A({1/cos A} + 1)]/ [sin A({1/cos A} - 1)] =... View Article

Find the mean of first ten odd natural numbers.

First ten odd natural numbers are:1, 3, 5, 7, 9, 11, 13, 15, 17, 19Mean = (1 + 3 + 5 + 7 + 9 + 11 + 13 + 15 + 17 + 19)/10= 100/10=... View Article

What is p2 + q2 formula?

Using the algebraic identity (a + b)2 = a2 + b2 + 2ab we can derive the formula as, (p + q)2 = p2 + q2 + 2pq Therefore, p2 + q2 = (p + q)2 - 2pq... View Article

Express sin A in terms of cot A.

We know that, cosec2A - cot2A = 1 cosec2A = 1 + cot2A 1/sin2A = 1 + cot2A So, sin2A = 1/(1 + cot2A) sin A = √[1/(1 + cot2A)]... View Article

Name the quadrilaterals whose diagonals are perpendicular bisectors of each other.

Rhombus and Square are the quadrilaterals whose diagonals are perpendicular bisectors of each other.... View Article

Find the derivative of sin2x with respect to x using product rule.

d/dx (sin2x) = d/dx (sin x. sin x)Using the product rule of differentiation,= sin x d/dx(sin x) + [d/dx (sin x)] sin x= sin x cos x + cos x sin... View Article