Answer:
0.25 kg
Step-by-step explanation:
Newton's second law states that:
![F=ma](https://img.qammunity.org/2020/formulas/physics/middle-school/hoqv0uuwk5hamoxytydy5e8slsjemaiqzz.png)
where
F is the net force acting on an object
m is the object's mass
a is its acceleration
In this problem, we have:
is the force exerted on the object
m is the ball's mass
is its acceleration
Solving the formula for m, we can find the ball's mass:
![m=(F)/(a)=(0.5 N)/(2.0 m/s^2)=0.25 kg](https://img.qammunity.org/2020/formulas/physics/middle-school/wpqhay9f4gm22e43tegi1smfwmt7zehu9o.png)