Karnataka Board - Class 9 previous year questions (PYQ)

Directions: In the question below, a statement of Assertion (A) is followed by a statement of Reason (R). Choose the correct option:

Assertion (A): Diamond sparkles brilliantly with internal radiance.

Reason (R): Total internal reflection of light occurs inside diamond because its critical angle is exceptionally small (approximately 24.4°).

Directions: In the question below, a statement of Assertion (A) is followed by a statement of Reason (R). Choose the correct option:

Assertion (A): The value of $\sin\theta$ cannot exceed 1 for any real angle $\theta$.

Reason (R): In any right-angled triangle, the hypotenuse is the strictly longest side, ensuring the ratio $\text{Perpendicular}/\text{Hypotenuse} \le 1$.

Directions: In the question below, a statement of Assertion (A) is followed by a statement of Reason (R). Choose the correct option:

Assertion (A): Electric current in a conductor is treated as a scalar physical quantity.

Reason (R): Although electric current has both magnitude and direction, it does not obey the laws of vector addition.

Refer to the Case Study 'Case Study: Parabolic Cable Geometry in Civil Engineering Suspension Bridges' to answer:

What is the vertical height of the suspension cable at a horizontal distance of $25\text{ m}$ from the bridge center?

Directions: In the question below, a statement of Assertion (A) is followed by a statement of Reason (R). Choose the correct option:

Assertion (A): If two linear equations represent coincident lines, the system has infinitely many solutions.

Reason (R): Two lines $a_1x + b_1y + c_1 = 0$ and $a_2x + b_2y + c_2 = 0$ coincide when $\frac{a_1}{a_2} = \frac{b_1}{b_2} = \frac{c_1}{c_2}$.