Answer:
0.5 kg
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:

It would be A because it would make sense
Answer:
The answer to your question is Pe = 2452.5 J
Explanation:
Data
mass = 50 kg
height = 5 m
gravity = 9.81 m/s²
Process
The energy of this process is Potential energy which is proportional to the mass of the body, the gravity and the height of the body.
Pe = mgh
Substitution
Pe = (50)(5)(9.81)
Simplification
Pe = 2452.5 J
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