You would want it to be greater than D. friction force
It needs be greater than the friction applied to it.
Answer: F = 20 N
Explanation:
I will ASSUME that the fulcrum is at the center of gravity of the lever arm, This means that the lever arm itself creates no moment about the fulcrum because there is no moment arm for that particular force.
To solve, we sum moments about any convenient point to zero (zero because there is no acceleration in the F = ma equation)
The easiest convenient point is the fulcrum
30((90/2) - 15) - F(90/2) = 0
30(30) = F(45)
F = 900/45 = 20 N
The answer is B
explanation
<span>I don't think there is enough information from the question. If you are asked to calculate the number of microbes in a certain area., then it should be that the total area or maybe the volume of that should be given so you can estimate the number of microbes. Hope this helps.</span>
