In a transistor, the collector current is 1 mA and base current 10 μA. Emitter current is MCQ with Answer and Explanation

Explanation:
P = V I, so watt = volt × ampere.

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:
T = 2π√(l/g): depends on l and g, independent of mass (gravitational and inertial mass cancel). Memory aid: 'Pendulum: T ∝ √(l/g); independent of mass for small angles'. Oscillations concept frequently tested in competitive exams.