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

Answer :

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

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

where:
- [tex]\( v \)[/tex] is the final speed of the hammer when it 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.

We need to solve for [tex]\( h \)[/tex]. Let's go through the steps:

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

2. Plug in the values for [tex]\( v \)[/tex] and [tex]\( g \)[/tex]:
[tex]\[ 8^2 = 2 \times 32 \times h \][/tex]

3. Calculate [tex]\( 8^2 \)[/tex]:
[tex]\[ 64 = 64h \][/tex]

4. Solve for [tex]\( h \)[/tex] by dividing both sides by 64:
[tex]\[ h = \frac{64}{64} = 1 \][/tex]

Thus, the hammer was 1.0 foot above the ground when you dropped it.

The correct answer is:
C. 1.0 foot