WAEC Physics 2023 Paper

Concept:Escape velocity is the minimum speed needed for an object to escape a planet's gravitational pull without further propulsion.Explanation:At the minimum escape speed, the object's kinetic energy just equals the gravitational potential energy required to leave the planet's surface.So, $\frac{1}{2}mv_e^2 = \frac{GMm}{R}$Cancel the mass $m$ from both sides.$v_e^2 = \frac{2GM}{R}$Take the square root of both sides.$v_e = \sqrt{\frac{2GM}{R}}$This is the correct standard expression for escape velocity.None of the listed options A–D is written correctly.Answer:$v_e = \sqrt{\frac{2GM}{R}}$