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A penny falls 380 meters. If dropped from rest, ignoring any air resistance, what is the velocity at which the penny hits the ground? Show your work.

User Subso
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1 Answer

1 vote

Answer:

Vf = 86.34 [m/s]

Step-by-step explanation:

To solve this problem we must use the following equation of kinematics.


v_(f) ^(2) =v_(o) ^(2) +2*g*y

where:

Vf = final velocity [m/s]

Vo = initial velocity = 0 (falls from the rest)

g = gravity acceleration = 9.81 [m/s²]

y = distance = 380 [m]

Vf² = 0 + (2*9.81*380)

Vf = 86.34 [m/s]

Note: The pisitive sign in the equation above means that the movement goes in the same direction of the gravity acceleration, therefore the velocity is increasing when the penny falls.

User Alexander Pletnev
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