Answered

The formula [tex]$T=2 \pi \sqrt{\frac{L}{32}}$[/tex] relates the time, [tex]$T$[/tex], in seconds for a pendulum with the length, [tex][tex]$L$[/tex][/tex], in feet, to make one full swing back and forth. What is the length of a pendulum that makes one full swing in 2.2 seconds? Use 3.14 for [tex]$\pi$[/tex].

A. 2 feet
B. 4 feet
C. 11 feet
D. 19 feet



Answer :

To determine the length [tex]\(L\)[/tex] of a pendulum given that the time [tex]\(T\)[/tex] for one full swing is 2.2 seconds, we start with the formula that relates the two variables:

[tex]\[ T = 2 \pi \sqrt{\frac{L}{32}} \][/tex]

Given:
- [tex]\(T = 2.2\)[/tex] seconds
- [tex]\(\pi = 3.14\)[/tex]

First, we need to solve this equation for [tex]\(L\)[/tex]. Here are the steps to isolate [tex]\(L\)[/tex].

1. Rearrange the formula to solve for [tex]\(\sqrt{\frac{L}{32}}\)[/tex]:
[tex]\[ \frac{T}{2 \pi} = \sqrt{\frac{L}{32}} \][/tex]

2. Substitute the values for [tex]\(T\)[/tex] and [tex]\(\pi\)[/tex]:
[tex]\[ \frac{2.2}{2 \times 3.14} = \sqrt{\frac{L}{32}} \][/tex]

3. Calculate [tex]\(\frac{2.2}{2 \times 3.14}\)[/tex]:
[tex]\[ \frac{2.2}{6.28} \approx 0.350318 \][/tex]

4. Square both sides to remove the square root:
[tex]\[ \left(0.350318\right)^2 = \frac{L}{32} \][/tex]
[tex]\[ 0.122723 \approx \frac{L}{32} \][/tex]

5. Multiply both sides of the equation by 32 to solve for [tex]\(L\)[/tex]:
[tex]\[ L = 32 \times 0.122723 \][/tex]
[tex]\[ L \approx 3.92714 \][/tex]

The length of the pendulum is approximately 3.927 feet.

Given the possible answers of 2 feet, 4 feet, 11 feet, and 19 feet, the closest value to our calculated length is 4 feet.

Thus, the length of the pendulum that makes one full swing in 2.2 seconds is approximately 4 feet.