Live practice

Choose a course and topic, attempt each question and open its complete worked solution when you are ready.

Reset
Question 1501
StructuredStandard4 marks
CBSE Class 11 Chemistry · Structure of Atom · Electromagnetic radiation and photoelectric effect

A 2 ns radiation pulse contains 2.5 × 10¹⁵ photons. Estimate the pulse energy by taking its characteristic frequency as the reciprocal of the pulse duration.

Question 1502
StructuredStandard3 marks
CBSE Class 11 Mathematics · Sets · Complement and set identities

Give sets \(A,B,C\) for which every pairwise intersection is non-empty but \(A\cap B\cap C=\varnothing\).

Question 1503
StructuredStandard5 marks
CBSE Class 11 Mathematics · Limits and Derivatives · Rules of differentiation

Differentiate 1/(ax²+bx+c).

Question 1504
StructuredStandard5 marks
CBSE Class 11 Mathematics · Straight Lines · Distance and intersections

Locate the points on the y-axis at distance 4 from \(\frac{x}{3}\)+\(\frac{y}{4}\)=1.

Question 1505
StructuredStandard5 marks
CBSE Class 11 Mathematics · Sequences and Series · Special series and applications

Three numbers in geometric progression sum to 56. Subtracting 1, 7 and 21 respectively makes an arithmetic progression. Determine the three numbers.

Question 1506
StructuredStandard4 marks
CBSE Class 11 Mathematics · Trigonometric Functions · Compound-angle identities

Complete every requested part of exercise 3.3, question 22: cot x cot 2x – cot 2x cot 3x – cot 3x cot x = 1 4tan x (1 − tan 2 x)

Question 1507
StructuredStandard5 marks
CBSE Class 11 Chemistry · Equilibrium · Acid-base equilibria and pH

The degree of ionization of a 0.1M bromoacetic acid solution is 0.132. Determine

(a)
the pH of the solution
(b)
the pKa of bromoacetic acid.
Question 1508
StructuredStandard5 marks
CBSE Class 11 Chemistry · Structure of Atom · Electromagnetic radiation and photoelectric effect

An absorption doublet occurs at 589.0 nm and 589.6 nm. Calculate

(a)
each frequency
(b)
the energy separation of the excited states.
Question 1509
StructuredStandard5 marks
CBSE Class 11 Mathematics · Conic Sections · Hyperbolas

For the hyperbola \(9y^2-4x^2=36\Rightarrow\frac{y^2}{4}-\frac{x^2}{9}=1\), determine its foci, vertices, eccentricity, and latus-rectum length.

Question 1510
StructuredStandard5 marks
CBSE Class 11 Mathematics · Limits and Derivatives · Rules of differentiation

Differentiate (ax+b)/(px²+qx+r).