Question

A piling for a high-rise building is pushed by two bulldozers at exactly the same time. One bulldozer exerts a force of 1250 pounds in a westerly direction. The other bulldozer pushes the piling with a force of 2650 pounds in a northerly direction. What is the magnitude of the resultant force upon the piling, to the nearest ten pounds? a. 2340 lbs. c. 3900 lbs. b. 2670 lbs. d. 2930 lbs.

Answer 1

Answer:

Option d is correct.

The magnitude of the resultant force upon the piling = 2930 lbs.

Explanation:

Resultant of a group of forces = vector sum of the forces.

Force 1 = (-1250î) lbs

Force 2 = (2650j) lbs

Resultant = (-1250î + 2650j) lbs

The magnitude of the resultant = √[(-1250)² + (2650)²] = 2930 lbs.

Or in visualization method, the two forces presented form a right angled triangle with the resultant of the two forces.

Hence, using Pythagoras theorem,

F₁² + F₂² = R²

(1250)² + (2650)² = R²

R = √[(1250)² + (2650)²] = 2930 lbs.