Question

20 ft. 10 ft. 50 lbs
25 lbs of force
40 lbs of force
60 lbs of force
75 lbs of force

Explanation:

Identify given values

We have a lever system.
The load weight is \(W = 50\text{ lbs}\).
The load arm distance is \(d_1 = 10\text{ ft}\).
The effort arm distance is \(d_2 = 20\text{ ft}\).

Apply torque balance

Using the Mechanical Advantage concept, the torque on both sides of the fulcrum must balance:

$$F \cdot d_2 = W \cdot d_1$$

Solve for effort force

Substitute the known values into the equation:

$$F \cdot 20 = 50 \cdot 10$$

$$20F = 500$$

$$F = 25\text{ lbs}$$

Answer:

• 25 lbs of force (Correct answer)
• 40 lbs of force
• 60 lbs of force
• 75 lbs of force