Question

The energy required to project a body of mass \(2\,\text{kg}\) so that it escapes from the gravitational influence of the earth is \[ (\text{Acceleration due to gravity on the surface of the earth}=10\,\text{m s}^{-2}\text{ and the radius of the earth}=6400\,\text{km}) \]

• A. \(96\times10^6\,\text{J}\)
• B. \(32\times10^6\,\text{J}\)
• C. \(128\times10^6\,\text{J}\)
• D. \(64\times10^6\,\text{J}\)

Hint:

Remember, \[ \boxed{ E_{\text{escape}}=mgR=\frac{GMm}{R}. } \] Also, \[ \boxed{ v_e=\sqrt{2gR}. } \]

Answer 1

The Correct Option is C