College

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. 16.0 feet
C. 8.0 feet
D. 1.0 foot

Answer :

To solve this problem, we need to find out how high the hammer was above the ground when it was dropped. We're given the formula for speed:

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

where:
- [tex]\( v \)[/tex] is the speed of the hammer when it hits the ground, which is 8 feet per second.
- [tex]\( g \)[/tex] is the acceleration due to gravity, which is 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]. Start by squaring both sides of the equation to eliminate the square root:

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

Now let's solve for [tex]\( h \)[/tex]:

1. Divide both sides by [tex]\( 2g \)[/tex]:

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

Now, plug in the given values:

- [tex]\( v = 8 \)[/tex] feet/second
- [tex]\( g = 32 \)[/tex] feet/second²

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

Calculate [tex]\( 8^2 \)[/tex]:

[tex]\[ 8^2 = 64 \][/tex]

Now, calculate the denominator:

[tex]\[ 2 \times 32 = 64 \][/tex]

Using these calculations, find [tex]\( h \)[/tex]:

[tex]\[ h = \frac{64}{64} = 1.0 \][/tex]

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

The correct answer is D. 1.0 foot.