Question

During a tour of a gold mine, visitors travel down a vertical mine shaft in an elevator. The speed of the elevator can be expressed as -5 feet per second. What is the position of the elevator with respect to the surface of the earth after 10 seconds?

Option 1: 50 feet above the surface
Option 2: 50 feet below the surface
Option 3: 10 feet above the surface
Option 4: 10 feet below the surface

Answer 1

The speed of the elevator indicates it is moving downward; after 10 seconds, it will be 50 feet below the surface of the earth.

Step-by-step explanation:

If the speed of the elevator is -5 feet per second, this indicates that the elevator is moving downwards at a rate of 5 feet per second. After 10 seconds, the elevator will have moved 10 seconds * 5 feet/second = 50 feet. Since the speed is given as a negative value, this means the elevator is moving away from the surface, hence, it is moving below the surface. Thus, the position of the elevator with respect to the surface of the earth after 10 seconds is 50 feet below the surface.