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Find the LCM of 8 and 30.

Prime factorization of 8 = 2 × 2 × 2 = 23Prime factorization of 30 = 2 × 3 × 5We know that LCM is the product of the... View Article

Solve the equation: modulus of (x – 1) = 1 – x.

modulus of (x - 1) = 1 - xThis can be written as:|x - 1| = 1 - xWe know that,|x - 1| = x - 1 for all x ≥ 1and|x - 1| = -(x - 1) for all x <... View Article

How to convert sin 80 into decimals?

We can write the value sin 80 degrees in decimals as follows:sin 80°= 0.9848077...This conversion can be done as given below:Let us convert... View Article

A parallel plate capacitor with air between the plates has a capacitance of 8 pF (1pF =10^{-12}F). What will be the capacitance if the distance between the plates is reduced by half, and the space between them is filled with a substance of dielectric constant 6?

Solution: Given: The capacitance of a parallel plate capacitor is 8 pF. Capacitance of the capacitor is given as: Where, Capacitance of the... View Article

Capacitance depends on which parameter/s?

a) Charge on capacitor b) Potential difference across capacitor c) Dielectric constant of the substance d) Area of plates e) Option c and d... View Article

A car is fitted with a convex side-view mirror of focal length 20 cm. A second car 2.8 m behind the first car is overtaking the first car at a relative speed of 15 m/s. The speed of the image of the second car as seen in the mirror of the first one is:

Solution: According to the mirror formula:... View Article

Express the HCF of 468 and 222 as 468x + 222y, where x and y are integers.

HCF of 468 and 222 is 6 468 = (222 × 2) + 24 222 = (24 × 9) + 6 24 = (6 × 4) + 0 Now we need to express HCF of 468... View Article

The volume of a sphere is 1.76 cm^3. The volume of 25 such spheres taking into account the significant figures is: A. 0.44 x 10^2 cu.cm B. 44.00 cu.cm C. 44.0 cu.cm D. 44 cu. cm

Answer: C. 44.0 cu.cm Given, volume of sphere = 1.76 cu.cm Volume of 25 spheres = 1.76 x 25 = 44 cm3 The volume of 25 such spheres taking... View Article

There are boys and girls in a class. The ratio of the number of boys to the total number of students in the class is:

Given, number of boys in a class = b number of girls in a class = g total number of students in a class = b+g Therefore, the ratio... View Article

Two fair dice are rolled simultaneously. The probability that 5 will come up at least once is:

Given, two dice are rolled simultaneously Total number of possible outcomes = 6 x 6 = 36 The outcomes of getting 5 at least once, are:... View Article

If the bisector of the vertical angle of a triangle bisects the base, prove that the triangle is isosceles.

Given, in △ABC, AD is a bisector of ∠A and meets base BC at D, such that: BD = DC... View Article

If matrix A is of order 3 x 2 and matrix B is of order 2 x 2 then the matrix AB is of order:

Given, Order of matrix A = 3 x 2 Order of matrix B = 2 x 2 Order of AB = Number of rows of A x Numbers of columns of B = 3 x 2... View Article

The price of sugar is increased by 20%. As a result, a family decreases its consumption by 25%. The expenditure of the family on sugar will be decreased by:

Let the price of sugar be Rs.100 Given, the price of sugar is increased by 20%. New price = Rs.120 Family decreased the consumption of... View Article

A card is drawn from a well shuffled deck of cards. What is the probability that the card drawn is neither a king nor a queen?

Total number of cards in a deck = 52 Number of cards with King and Queen = 4 + 4 = 8 Number of cards that are neither King nor Queen = 52 - 8... View Article

If sum of two numbers is 1215 and their HCF is 81, then the possible number of pairs of such numbers are:

Given, Sum of two numbers = 1215 Let the numbers be x and y. Also, HCF (x, y) = 81 So, 81 x + 81 y = 1215 x + y = 1215/81 x... View Article

The HCF and LCM of two numbers are 33 and 264 respectively. When the first number is completely divided by 2 the quotient is 33. the other number is:

Answer: HCF - The largest common divisor or gcd of two or more positive integers, as the mathematics rules dictate, appears to be the largest... View Article

When 1- Methylcyclohexene is treated with HCL it produces:

(A) 1-Chloro-cyclohexane (B) 1-Chloro-2-methylcyclohexane (C) 1-Chloro-1-methylcyclohexane (D) 2-Chloro-1-methylcyclohexane The Correct... View Article

An element with a molar mass of 27 g/mol forms a cubic unit cell with an edge length of 4.05 * 10-8 cm. If the density of the element is 2.7 g/cm-3. What will be the nature of a cubic unit cell?

(A) Face Centred Cubic (FCC) (B) Cubic-Close packed (CCP) (C) Body-Centred Cubic (BCC) (D) Both (A)and (B) The Correct Answer is (D) Both... View Article

Standard entropy of X2, Y2 and XY3 are 60, 40 and 50 ZJK-1 mol-1, respectively. For the reaction, 1/2X2 + 3/2Y2 → XY3 ; △h =-30kj to be at equilibrium. What will be the temperature?

(A) 500 K (B) 750 K (C) 1000 K (D) 1250 K The Correct Answer is (B) 750 K Solution: 1000 * (-60) = -80 * T Explore more such... View Article

One mole of an ideal gas expands reversibly at a constant temperature of 300 k from an initial volume of 10 lit to a final volume of 20 lit. What will be the work done in expanding the gas?

(A) 750J (B) 1500J (C) 1728J (D) 3456J The Correct Answer is (C) 1728J Solution: As given: Temperature, t =300 k Volume, V1 = 10lit... View Article