Final answer:
The correct choice for determining the resultant force on the screw eye is Option 3: the square root of the sum of the squares of the horizontal and vertical forces. This uses the Pythagorean theorem as both forces are perpendicular to each other.
Step-by-step explanation:
To determine the resultant force on the screw eye when one rope is horizontal and the other is vertical, and both ropes experience a force of 175 lb, we must apply the principles of vector addition. Given that force is a vector quantity with both magnitude and direction, the resultant force can be found by adding the individual vectors along their respective axes. Since one force is horizontal and the other is vertical, they are perpendicular to each other.
Option 3 is the correct choice: The resultant force on the screw eye is the square root of the sum of the squares of the horizontal and vertical forces. According to the Pythagorean theorem, this means that if both the horizontal and vertical components of the force are 175 lb each, the resultant force R can be calculated as R = √(175^2 + 175^2), which yields a value greater than 175 lb.