The power used by Alex to drag the log across the yard is determined as 2,656 W.
<h3>Mass of the log</h3>
The mass of the log is calculated as follows;
W = mg
m = W/g
m = (400)/9.8
m = 40.82 kg
<h3>Velocity of the log</h3>
K.E = ¹/₂mv²
v² = 2K.E/m
v² = (2 x 900)/(40.82)
v² = 44.096
v = 6.64 m/s
<h3>Power used by Alex</h3>
P = Fv
P = 400 x 6.64
P = 2,656 W
Learn more about power here: brainly.com/question/13881533
#SPJ1
Answer:
Buffer B has the highest buffer capacity.
Buffer C has the lowest buffer capacity.
Explanation:
An effective weak acid-conjugate base buffer should have pH equal to 
of the weak acid. For buffers with the same pH, higher the concentrations of the components in a buffer, higher will the buffer capacity.
Acetic acid is a weak acid and 
is the conjugate base So, all the given buffers are weak acid-conjugate base buffers. The pH of these buffers are expressed as (Henderson-Hasselbalch):
![pH=pK_{a}(CH_{3}COOH)+log\frac{[CH_{3}COO^{-}]}{[CH_{3}COOH]}](https://tex.z-dn.net/?f=pH%3DpK_%7Ba%7D%28CH_%7B3%7DCOOH%29%2Blog%5Cfrac%7B%5BCH_%7B3%7DCOO%5E%7B-%7D%5D%7D%7B%5BCH_%7B3%7DCOOH%5D%7D)
Buffer A: 
Buffer B: 
Buffer C: 
So, both buffer A and buffer B has same pH value which is also equal to . Buffer B has higher concentrations of the components as compared to buffer A, Hence, buffer B has the highest buffer capacity.
The pH of buffer C is far away from . Therefore, buffer C has the lowest buffer capacity.
Normal rainwater has a pH of 5.6<span> (slightly acidic)</span>
