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{2 g h} [/tex]

A. 16.0 feet
B. 0.5 feet
C. 0.25 feet
D. 1.0 foot

Answer :

To solve the problem of finding out how far above the ground the hammer was dropped from, we can use the formula:

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

where:
- [tex]\( v \)[/tex] is the velocity at which the hammer hits the ground (4 feet per second),
- [tex]\( g \)[/tex] is the acceleration due to gravity (32 feet/second²),
- [tex]\( h \)[/tex] is the height from which the hammer was dropped.

We need to rearrange this formula to solve for [tex]\( h \)[/tex]. Here's how you can do it step-by-step:

1. Start with the formula:
[tex]\[ v = \sqrt{2gh} \][/tex]

2. Square both sides of the equation to eliminate the square root:
[tex]\[ v^2 = 2gh \][/tex]

3. Solve for [tex]\( h \)[/tex] by dividing both sides by [tex]\( 2g \)[/tex]:
[tex]\[ h = \frac{v^2}{2g} \][/tex]

4. Substitute the known values into the equation:
- [tex]\( v = 4 \)[/tex] feet/second
- [tex]\( g = 32 \)[/tex] feet/second²

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

5. Calculate the value:
- [tex]\( 4^2 = 16 \)[/tex]
- [tex]\( 2 \times 32 = 64 \)[/tex]
- [tex]\( \frac{16}{64} = 0.25 \)[/tex]

The height ([tex]\( h \)[/tex]) from which the hammer was dropped is 0.25 feet above the ground.

Therefore, the correct answer is C. 0.25 feet.