Answer:
0.5 kg
Step-by-step explanation:
The momentum of an object is defined as
p = mv
where
m is the mass
v is the velocity
In this problem we have,
v = 15 m/s is the velocity of the stone
p = 7.5 kg m/s is the momentum
Solving for m, we can find the mass of the stone:
![m=(p)/(v)=(7.5 kg m/s)/(15 m/s)=0.5 kg](https://img.qammunity.org/2020/formulas/physics/middle-school/nglb5j8173rqdjey37cgqes8no2u9n9eyj.png)