2 arms of a u-tube are not identical, one having twice the diameter of the other. a cork in the narrow arm requires a force of 16n to remove it. the tube is filled with water and the wide arm is fitted with a piston. the min force that must be applied to the piston to push out cork is?
The Attempt at a Solution
p1=f1/(pi*r^2), p2=f/pi*2r^2, p1=p2, f1/(pi*r^2)=f2/(pi*2r^2)....f2=(pi*r^2)*f1/(pi*r^2) which gives me 32. The answer is actually 64. What am i missing?