Beats observable when frequencies are: MCQ with Answer and Explanation

Explanation:
Surface tension is defined as Force per unit length (F/L). Dimensional formula: [MLT⁻²] / [L] = [MT⁻²]. A spring constant (k) is defined by Hooke's Law as Force per unit extension (F/x), which also has dimensions [MLT⁻²] / [L] = [MT⁻²]. Thus, both share the same dimensional formula.

Explanation:
Lightning rod uses sharp point to facilitate corona discharge, neutralizing charge to prevent lightning strike.

Explanation:
2 protons + 2 neutrons, charge +2e.