An electric device delivers a current of [tex]$15.0 A$[/tex] for 30 seconds. How many electrons flow through it?
Answer (1)
Calculate the ratio of base distance to height for each option.
Determine that the generally accepted safe ratio for ladder setup is 4:1, meaning the base should be 1/4 of the height.
Compare the calculated ratios to the safe ratio.
Identify the option that matches the 4:1 rule: B .
Explanation
Analyze the problem The question asks us to identify the correct base-to-wall distance for setting up a ladder safely. We need to evaluate each option and determine which one adheres to the recommended safety guidelines.
Calculate the ratios Let's analyze each option:
Option A: The base should be 2 feet from the wall for every 4 feet of height. This gives a ratio of base distance to height of 4 2 = 0.5 .
Option B: The base should be 1 foot from the wall for every 4 feet of height. This gives a ratio of base distance to height of 4 1 = 0.25 .
Option C: The base should be 5 feet from the wall for every 4 feet of height. This gives a ratio of base distance to height of 4 5 = 1.25 .
Option D: The base should be 3 feet from the wall for every 5 feet of height. This gives a ratio of base distance to height of 5 3 = 0.6 .
Determine the correct ratio The generally accepted safe ratio for ladder setup is the 4:1 rule. This means for every 4 feet of vertical height, the base of the ladder should be 1 foot away from the wall. Therefore, the base distance should be 4 1 of the height, which is a ratio of 0.25.
Select the correct option Comparing the ratios, Option B ( 4 1 = 0.25 ) matches the 4:1 rule. Therefore, the correct answer is that the base should be 1 foot from the wall for every 4 feet of height.
Examples
Understanding the correct ladder setup is crucial in various real-life scenarios, such as home maintenance, construction, and even decorating. For instance, when putting up holiday lights, knowing the 4:1 rule ensures the ladder is stable and prevents accidents. Similarly, in construction, workers rely on this principle to safely access elevated areas. By adhering to this guideline, individuals can significantly reduce the risk of falls and injuries, making tasks safer and more efficient.
