Question

The escape velocity on the surface of a planet is $V_e$ what would be the escape velocity on the planet having the same radius but mass 4 times that of it.

• A. 2 $V_e$
• B. 4 $V_e$
• C. $V_e$
• D. $\frac{V_e}{2}$

Answer 1

The correct option is A 2 $V_e$

The equation for the escape velocity of a planet in our solar System is:

v(e)= (2GM/R)^1/2. Your example would change the equation to:

v(e)=(2G*4M/3R)^1/2 so when you cancel the threes you get v(e)=(2GM/R)^1/2 = 2V(e)