The time period of a geostationary satellite is: MCQ with Answer and Explanation

Explanation:
The velocity of sound in a medium is determined by the formula v = √(E/ρ), where E is the modulus of elasticity and ρ is the density. Although solids are denser, their modulus of elasticity (bulk modulus) is tremendously higher than that of gases, overwhelmingly compensating for the density. Hence, sound travels fastest in solids.

Explanation:
Energy = 0.04 kW × 8 h = 0.32 kWh.

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'.