Answer
(a) $I = 7.0~kg\cdot m^2$
(b) $I = 0.70~kg\cdot m^2$
(c) It would be harder to accelerate this array about the y axis because the moment of inertia about the y axis is larger.
Work Step by Step
(a) We can calculate the moment of inertia about the y axis.
$I = (2.2~kg)(0.50~m)^2 + (2.2~kg)(1.00~m)^2 + (3.4~kg)(0.50~m)^2 + (3.4~kg)(1.00~m)^2$
$I = 7.0~kg\cdot m^2$
(b) We can calculate the moment of inertia about the x axis.
$I = (2.2~kg)(0.25~m)^2 + (2.2~kg)(0.25~m)^2 + (3.4~kg)(0.25~m)^2 + (3.4~kg)(0.25~m)^2$
$I = (11.2~kg)(0.25~m)^2$
$I = 0.70~kg\cdot m^2$
(c) It would be harder to accelerate this array about the y axis because the moment of inertia about the y axis is larger.
