Posted by Akbar on .
In a hydraulic lift, the radii of the pistons are 2.93 cm and 10.1 cm. A car weighing W = 11.0 kN is to be lifted by the force of the large piston.
(a) What force Fa must be applied to the small piston? 925.7 N
(b) When the small piston is pushed in by 10.4 cm, how far is the car lifted? mm
b. h2 = h1•(A1/A2) = h1•(r/R) = 3.02 cm
(c) Find the mechanical advantage of the lift, which is the ratio W / Fa.
11.9
Sorry for reposting, but i don't know why part b is wrong the answer has to be in mm, so 3.02 cm would be 30.2 mm, but it giving me wrong; please help. Thank you.

physics 
bobpursley,
part b is wrong because you did (A1/A2)=(r/R)
the ratio of radii should be squared... 
physics 
Akbar,
Thank you!