A man uses a 11-foot bar to lift a 108-pound tire. He places a rock 2 feet from the tire to act as the fulcrum. How much force must he exert to lift the tire?
A) 108 lb
B) 12 lb
C) 24 lb
D) 9 lb

Question

Quizplus · Accepted Answer

To solve this problem, we can use the formula: weight x distance = force x distance.

First, we need to find the distance from the rock to the tire, which is 9 feet (11 feet - 2 feet).

Next, we plug in the values we know:

108 lb x 9 ft = force x 2 ft

Simplifying:

force = (108 lb x 9 ft) / 2 ft

force = 972 lb-ft/2 ft

force = 486 lb

Therefore, the man must exert a force of 486 pounds to lift the tire. The closest answer choice is C, 24 lb, which is not the actual force required to lift the tire. The answer is not A, because the weight of the tire is being lifted, and the man must exert more force than the weight of the tire due to the length of the bar and the placement of the fulcrum. The answer is not B or D, as those values are too low to match the actual force required.

A Man Uses a 11-Foot Bar to Lift a 108-Pound