Clarify what you mean by ratios?
Answer:

Explanation:
Given that,
The instantaneous current in the circuit is giveen by :

We need to find the rms value of the current.
The general equation of current is given by :

It means, 
We know that,

So, the rms value of current is 2.12 A.
The buoyant force or upward buoyancy force
The average power supplied to the box by friction while it slows from 13 m/s to 11.5 m/s is 3.24 W.
<h3>Acceleration of the box</h3>
The acceleration of the box is calculated as follows;
vf² = vi² + 2as
a = (vf² - vi²)/2s
a = (11.5² - 13²) / (2 x 8.5)
a = -2.16 m/s²
<h3>Time of motion of the box</h3>
The time taken for the box to travel is calculated as follows;
a = (vf - vi)/t
t = (vf - vi) / a
t = (11.5 - 13) / (-2.16)
t = 0.69 s
<h3>Average power supplied by the friction</h3>
P = Fv
P = (ma)(vf - vi)
P = (1 x -2.16) x (11.5 - 13)
P = 3.24 W
Thus, the average power supplied to the box by friction while it slows from 13 m/s to 11.5 m/s is 3.24 W.
Learn more about average power here: brainly.com/question/19415290
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