1. The problem statement, all variables and given/known data Choose two masses and vary their separation, measuring the force between them each time. Plot a straight line graph and use the gradient to estimate the universal gravitational constant. Include uncertainties in the results and express values with the appropriate number of significant figures. Im stumped...i could simply solve for G by inputing the variables i have (all except G) but i have to use the gradient of the graph. 2. Relevant equations F= G*Mm/r^2 F=1/r^2 3. The attempt at a solution i tried graphing Force vs 1/distance^2 and using the slope of it.