The energy equivalent of 1 g mass is MCQ with Answer and Explanation

Explanation:
Dispersion happens because refractive index varies with wavelength. Prism, rainbow. Scattering is Tyndall effect (blue sky). Polarisation restricts vibrations.

Explanation:
P = 1/f(m) ⇒ f = 1/P = 1/(-4) = -0.25 m = -25 cm. Negative focal length indicates diverging (concave) lens. Memory aid: 'Negative power = concave lens; f(cm) = 100/P(D)'. Direct lens power application frequently tested in competitive exams with sign convention awareness.

Explanation:
Three significant figures require the number to be written with three meaningful digits. 3.00 × 10⁸ m/s has three significant figures (3,0,0). 3 × 10⁸ has one significant figure; 3.0 × 10⁸ has two; 300000000 has ambiguous significance. Standard scientific notation: 3.00 × 10⁸ m/s. This is important in precision measurements.