High School

Suppose an elevator in the Empire State Building weighs 1900 pounds. Find the work \( W \) required to raise the elevator from ground level to story number 96, which is 1152 feet above the ground level.

A. 215,808 ft-lb
B. 231,600 ft-lb
C. 252,192 ft-lb
D. 269,424 ft-lb

Answer :

Final answer:

The calculation for the work required to raise a 1900-pound elevator 1152 feet resulted in a value that does not match any of the provided answer options. The correct option is not listed here.

Explanation:

To determine the work done to raise an elevator, we can use the formula for work, which is the product of force and displacement in the direction of the force. Here, the force is due to gravity and is equal to the weight of the elevator, and the displacement is the vertical distance the elevator travels.

First, we need to convert the weight of the elevator from pounds to newtons because work is typically expressed in joules (newtons multiplied by meters). However, since the answer choices provided are in foot-pounds, we can stay with imperial units. Therefore, we can calculate work using the following steps:

  1. Work (W) = Weight (F) × Distance (d)
  2. W = 1900 lbs × 1152 feet
  3. W = 2,188,800 foot-pounds

This value is not matching any of the answer options provided, suggesting there may be an error in the original question or in the conversion between units. Let's confirm by converting 1900 lbs to newtons and 1152 feet to meters to cross-check with the metric system:

  1. 1 pound ≈ 4.44822 newtons
  2. 1900 lbs ≈ 8456.418 newtons
  3. 1 foot ≈ 0.3048 meters
  4. 1152 feet ≈ 351.1 meters
  5. Work (W) = 8456.418 N × 351.1 m
  6. W ≈ 2,970,179.658 J

After performing the conversion, we see that the work in joules is also not matching any of the provided options, which confirms the discrepancy. Thus, based on the data provided, the work required to raise the elevator cannot be accurately determined with the given options.