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. 1.0 foot
B. 2.0 feet
C. 8.0 feet
D. 16.0 feet

Answer :

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

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

where:
- [tex]\( v \)[/tex] is the final velocity when the hammer hits the ground, 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 from which the hammer was dropped, and it is what we need to find.

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

1. Start by squaring both sides of the equation to get rid of the square root:

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

2. Plug in the given values:

[tex]\[ 8^2 = 2 \times 32 \times h \][/tex]

3. Simplify the left side of the equation:

[tex]\[ 64 = 64h \][/tex]

4. Solve for [tex]\( h \)[/tex] by dividing both sides by 64:

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

5. So, [tex]\( h = 1.0 \)[/tex] foot.

Therefore, the hammer was dropped from a height of 1.0 foot above the ground. The correct answer is A. 1.0 foot.