Answer
The correct answer is:
B. $6.7~m/s$
Work Step by Step
We can find the speed of the $0.50~kg$ ball after the acceleration period:
$v_f = v_0+at$
$v_f = 0+(10~m/s^2)(2.0~s)$
$v_f = 20~m/s$
We can use conservation of momentum to find the final speed $v$ of the balls after the collision:
$(0.50~kg+1.0~kg)~v = (0.50~kg)(20~m/s)$
$v = \frac{(0.50~kg)(20~m/s)}{1.5~kg}$
$v = 6.7~m/s$
The correct answer is:
B. $6.7~m/s$
