A hammer is accidentally dropped from rest down a vertical mine shaft. How long does it take for the rock to reach a depth of 79 m? Neglect air resistance.
A)2.8 s
B)9.0 s
C)8.0 s
D)4.9 s
E)4.0 s

Question

Quizplus · Accepted Answer

The time it takes for an object to fall a certain distance under gravity can be calculated using the formula $ t = \sqrt{\frac{2d}{g}} $, where $ d $ is the distance (79 m) and $ g $ is the acceleration due to gravity (approximately 9.8 m/s²). Plugging in the values, $ t = \sqrt{\frac{2 \times 79}{9.8}} \approx 4.0 $ seconds.

A Hammer Is Accidentally Dropped from Rest Down a Vertical