NEIEP Mechanics Practice Exam

How many gallons of oil are necessary to raise a 4-inch plunger 25 feet?

1. 10.7 gallons

2. 12.5 gallons

3. 16.3 gallons

4. 20.0 gallons

The correct answer is: 16.3 gallons

To determine how many gallons of oil are necessary to raise a 4-inch plunger 25 feet, you first need to understand the relationship between the volume of oil, the dimensions of the plunger, and the distance it will travel. The volume of oil needed is calculated using the formula for the volume of a cylinder, which is given by the area of the base multiplied by the height. The base area for the plunger can be calculated using the radius (half of the diameter). Given that the plunger has a diameter of 4 inches, the radius is 2 inches. To convert this into feet, remember that there are 12 inches in a foot, so the radius in feet is 2 inches divided by 12, resulting in approximately 0.1667 feet. The area of the base is then calculated using the formula for the area of a circle (πr²). Once you have the base area, multiply it by the height (25 feet) to find the total volume of the oil needed in cubic feet. After calculating the total volume in cubic feet, this needs to be converted to gallons, with the knowledge that 1 cubic foot is equivalent to approximately 7.48 gallons. After performing