A sound wave has wavelength 1.7 m and speed 340 m/s. Its frequency is MCQ with Answer and Explanation

Explanation:
Relative error = (Absolute error) / (Measured value) = 0.005 / 12.345 ≈ 0.000405. Converting to percentage: 0.000405 × 100% ≈ 0.0405% ≈ 0.04%. Relative error quantifies precision independent of measurement scale. Absolute error (±0.005) indicates instrument precision. This concept is vital for comparing measurement reliability across different magnitudes. Memory tip: Percentage error = (Absolute error / True value) × 100. Competitive exams often test this calculation with varying significant figures to assess numerical proficiency.

Explanation:
Seconds pendulum has time period of 2 seconds (1 s for half swing). Frequency f = 1/T = 1/2 = 0.5 Hz. Length about 99.4 cm on Earth. Not exactly 1 m.

Explanation:
Generator: coil rotated in magnetic field induces emf. Motor: opposite. Transformer: changes voltage, no moving parts. Rectifier: AC to DC.