The effort of a Porter governor is equal to (where c = Percentage increase in speed, m = Mass of ball and M = Mass on the sleeve)
A
$${\text{c}}\left( {{\text{m}} - {\text{M}}} \right){\text{g}}$$
B
$${\text{c}}\left( {{\text{m}} + {\text{M}}} \right){\text{g}}$$
C
$$\frac{{\text{c}}}{{\left( {{\text{m}} + {\text{M}}} \right){\text{g}}}}$$
D
$$\frac{{\text{c}}}{{\left( {{\text{m}} - {\text{M}}} \right){\text{g}}}}$$
Correct Answer: $${\text{c}}\left( {{\text{m}} + {\text{M}}} \right){\text{g}}$$