A. is a neutral substance a pH of 7 describes something of neutral pH where anything less than 7 is an acid and higher is a base
That is true Step by step:
Answer:
time=4s
Explanation:
we know that in a RL circuit with a resistance R, an inductance L and a battery of emf E, the current (i) will vary in following fashion
, where
max=
Given that, at i(2)=
⇒
⇒
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Applying logarithm on both sides,
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Now substitute 
⇒
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Applying logarithm on both sides,
⇒
⇒
⇒
now subs. 
⇒
also 
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V=IR so voltage is directly proportional to current. So for a given resistance increasing the voltage will result in a high current as well. This is because resistance is proportional to the voltage over the current. Ex: I=V/R
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