What is the minimum force required to prevent a ball weighing 22.6 lb from rolling down a ramp which is inclined at 39.0 degrees with the horizontal? a. 7.1 lb b. 8.8 lb c. 17.6 lb d. 14.2 lb

The correct answer is 14.2 lb which is choice D.

Let:

F = minimum force required to prevent ball from rolling down the ramp

The formula will be:

F = w * sin theta

F = w * sin (39 degrees)

F = 22.6 * sin (39) 
= 14.2 lb (this is rounded to the nearest tenth)

C. expression because any expression or equation may contain more than one variable

The answer to your question is d 68%