High School

You are helping with some repairs at home. You drop a hammer, and it hits the floor at a speed of 8 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. 8.0 feet
B. 2.0 feet
C. 1.0 foot
D. 16.0 feet

Answer :

To find out how far above the ground the hammer was when you dropped it, we can use the formula:

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

where:
- [tex]\( v \)[/tex] is the speed at which the hammer hits the floor, which is 8 feet per second.
- [tex]\( g \)[/tex] is the acceleration due to gravity, which is 32 feet per second squared.
- [tex]\( h \)[/tex] is the height we want to find.

Let's solve the formula for [tex]\( h \)[/tex]:

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

2. Square both sides to get rid of 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 given values into the equation:
[tex]\[ h = \frac{8^2}{2 \times 32} \][/tex]

5. Calculate:
[tex]\[ h = \frac{64}{64} = 1.0 \][/tex]

So, the height [tex]\( h \)[/tex] from which the hammer was dropped is 1.0 foot.

Thus, the correct option is C. 1.0 foot.