Answer:
option A
Explanation:
given,
height of the drop of stone = 9.44 m
speed of the stone = ?
As the stone is dropped the energy of the stone will be conserved.
using conservation of energy.
Potential energy = Kinetic energy

v = 13.60 m/s
Hence, the correct answer is option A
The intensity of a sound wave is defined as the amount of energy passing through a unit area of the wave front in unit of time.
According to the law of conservation of momentum:

m1 = mass of first object
m2 = mass of second object
v1 = Velocity of the first object before the collision
v2 = Velocity of the second object before the collision
v'1 = Velocity of the first object after the collision
v'2 = Velocity of the second object after the collision
Now how do you solve for the velocity of the second car after the collision? First thing you do is get your given and fill in what you know in the equation and solve for what you do not know.
m1 = 125 kg v1 = 12m/s v'1 = -12.5m/s
m2 = 235kg v2 = -13m/s v'2 = ?




Transpose everything on the side of the unknown to isolate the unknown. Do not forget to do the opposite operation.




The velocity of the 2nd car after the collision is
0.03m/s.
Answer:
zero
rank the magnitude of the average velocity over the first 2 second
Your answer is 632,100J which is Choice D