Question

plz give answer fast​

Answer 1

We know that,
$escape \: velocity \: of \: earth \: = \sqrt{ \frac{2gm}{r} }$

Now,
$escape \: velocity \: of \: planet = \sqrt{ \frac{2g(8m)}{2r} }$

$escape \: velocity \: of \: planet = \sqrt{ \frac{(4)2gm}{r} }$

$escape \: velocity \: of \: planet = 2\sqrt{\frac{2gm}{r} }$

$escape \: velocity \: of \: planet$
$= 2 \: (escape \: velocity \: of \: earth)$