The weight of a body is zero when it is MCQ with Answer and Explanation

Explanation:
Femto (f) = 10⁻¹⁵. Pico (p) = 10⁻¹², nano (n) = 10⁻⁹, atto (a) = 10⁻¹⁸. The prefix chain: milli 10⁻³, micro 10⁻⁶, nano 10⁻⁹, pico 10⁻¹², femto 10⁻¹⁵, atto 10⁻¹⁸. Mnemonic: Femto is 'fifteen'.

Explanation:
Solar cell (photovoltaic cell) generates electricity from sunlight.

Explanation:
Louis de Broglie proposed that matter exhibits wave-like properties. The de Broglie wavelength (lambda) of a particle is given by the formula lambda = h / p, where 'h' is Planck's constant and 'p' is the linear momentum (mass * velocity) of the particle. Therefore, the wavelength is strictly inversely proportional to the momentum of the moving particle.