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. 1.0 foot
C. 8.0 feet
D. 16.0 feet

Answer :

To find how far above the ground the hammer was when you dropped it, we can use the formula for velocity in terms of gravity and height:

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

where:
- [tex]\( v \)[/tex] is the velocity when the hammer hits the ground,
- [tex]\( g \)[/tex] is the acceleration due to gravity,
- [tex]\( h \)[/tex] is the height from which the hammer was dropped.

We are given:
- The velocity [tex]\( v = 8 \)[/tex] feet per second,
- The acceleration due to gravity [tex]\( g = 32 \)[/tex] feet/second².

We need to solve for [tex]\( h \)[/tex]. First, we'll rearrange the formula to solve for [tex]\( h \)[/tex]:

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

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

Substitute the given values into the equation:

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

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

[tex]\[ h = 1.0 \, \text{foot} \][/tex]

Therefore, the hammer was 1.0 foot above the ground when it was dropped. Thus, the correct answer is B. 1.0 foot.