What would be the value of g on the surface of the earth if its mass was twice as large and its radius half of what if is now?

Explanation

Given: `M'=2M`
`R'=R/2`
To find: `g=?`
Formula: `g=(GM)/(R^(2))`
Solution `g'=(GM')/(R^('2))`
`=(Gxx2M)/((R/2)^(2))=(Gxx2M)/((R^(2))/4)=(4xx2xxGM)/(R^(2))`
`=4xx2xxg………..(g=(GM)/(R^(2)))`
`g'=8g`
The valueof g will become 8 times.