The escape velocity of a body on a planet A is 12 km s - 1 . The escape velocity of the body on another planet B , whose density is four times and radius is half of the planet A , is

Step-by-step solution

We know that escape velocity is given by, v = 2 G M R ⇒ v A v B = M A M B × R B R A = ρ A R A 3 ρ B R B 3 × R B R A = ρ A R A 2 ρ B R B 2 = 1 4 × 4 1 ⇒ v B = v A = 12   km   s - 1