College

You are helping with some repairs at home. You drop a hammer, and it hits the floor at a speed of 12 feet per second. If the acceleration due to gravity [tex](g)[/tex] is 32 feet/second[tex]\(^2\)[/tex], how far above the ground [tex](h)[/tex] was the hammer when you dropped it? Use the formula:

[tex]\[ v = \sqrt{2gh} \][/tex]

A. 2.25 feet
B. 8.5 feet
C. 18.0 feet
D. 1.0 foot

Answer :

We are given the formula

[tex]$$
v = \sqrt{2gh},
$$[/tex]

where:
- [tex]$v$[/tex] is the final speed (12 ft/s),
- [tex]$g$[/tex] is the acceleration due to gravity (32 ft/s[tex]$^2$[/tex]), and
- [tex]$h$[/tex] is the height.

To find [tex]$h$[/tex], we first square both sides of the equation:

[tex]$$
v^2 = 2gh.
$$[/tex]

Now, solve for [tex]$h$[/tex] by dividing both sides by [tex]$2g$[/tex]:

[tex]$$
h = \frac{v^2}{2g}.
$$[/tex]

Substitute the given values:

[tex]$$
v^2 = 12^2 = 144,
$$[/tex]

and

[tex]$$
2g = 2 \times 32 = 64.
$$[/tex]

Thus,

[tex]$$
h = \frac{144}{64} = 2.25 \text{ feet}.
$$[/tex]

So, the hammer was dropped from a height of [tex]$\boxed{2.25\ \text{feet}}$[/tex], which corresponds to option A.