College

You are helping with some repairs at home. You drop a hammer, and it hits the floor at a speed of 4 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. 1.0 foot
B. 16.0 feet
C. 0.25 feet
D. 0.5 feet

Answer :

To solve this problem, we need to find out how high above the ground the hammer was when you dropped it. We're given the speed at which the hammer hits the floor (4 feet per second) and the acceleration due to gravity (32 feet/second²).

We can use the formula:

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

where:
- [tex]\( v \)[/tex] is the final speed (4 feet per second),
- [tex]\( g \)[/tex] is the acceleration due to gravity (32 feet/second²),
- [tex]\( h \)[/tex] is the height we need to find.

First, we'll rearrange the formula to solve for [tex]\( h \)[/tex]:

1. Square both sides to eliminate the square root:

[tex]\[ v^2 = 2gh \][/tex]

2. Solve for [tex]\( h \)[/tex]:

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

Now, plug in the known values:

- [tex]\( v = 4 \)[/tex] feet per second
- [tex]\( g = 32 \)[/tex] feet/second²

Substitute these into the formula:

[tex]\[ h = \frac{4^2}{2 \times 32} \][/tex]

[tex]\[ h = \frac{16}{64} \][/tex]

[tex]\[ h = 0.25 \][/tex] feet

So the height from which the hammer was dropped is 0.25 feet. Therefore, the correct answer is option C: 0.25 feet.