## Physics for Scientists and Engineers: A Strategic Approach with Modern Physics (3rd Edition)

$m = 89.3~kg$
We can find the acceleration of the system. $y = \frac{1}{2}at^2$ $a = \frac{2y}{t^2}$ $a = \frac{(2)(1.0~m)}{(6.0~s)^2}$ $a = 0.0556~m/s^2$ Let's consider the system of both blocks. The weight of the block of mass $m$ pulls down on the left while the weight of the 100-kg block pulls down on the right. We can use a force equation to find $m$. $\sum F = (m+100~kg)~a$ $(100~kg)~g-mg = (m+100~kg)~a$ $m = \frac{(100~kg)(g-a)}{g+a}$ $m = \frac{(100~kg)(9.80~m/s^2-0.0556~m/s^2)}{9.80~m/s^2+0.556~m/s^2}$ $m = 89.3~kg$