The focal length of a concave mirror is 15 cm. The radius of curvature is MCQ with Answer and Explanation

Explanation:
Ideal solenoid interior has uniform magnetic field B = μ₀ n I, parallel to axis. Outside field weak. Used in electromagnets, relays. Uniformity for scientific instruments.

Explanation:
Raman effect discovered in 1928, Nobel in 1930.

Explanation:
In uniform circular motion, the magnitude of velocity (speed) remains constant. However, the direction of motion is continuously changing tangentially at every point on the circular path. Since velocity is a vector quantity (requiring both magnitude and direction), a change in direction means the velocity is changing continuously, resulting in an accelerated motion.