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3 years ago

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An electrician must decide between 3 heaters. The wire that she is using is rated 15A maximum, anything beyond that is a fire ha

zard. Two of the heaters operate off a standard 120V circuit. One is rated 900W and the other 1800W. The third operates off a 240V circuit and can deliver 3000W of power. Calculate the amount of current for each.

1 answer:

lutik1710 [3]3 years ago

6 0

Use the formula: $P=IV$ , where P is power (watts), I is current (amperes) and V is potential difference (volts).

For the first heater:
$900W = I_{1}*120V$
$I_{1} = 7.5A$

For the second heater:
$1800W = I_{2}*120V$
$I_{2} = 15A$

For the third heater:
$3000W = I_{3}*240V$
$I_{3} = 12.5A$

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Jack and Jill are on two different floors of their high rise office building and looking out of their respective windows. Jack s

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The formula is

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Answer:

$T_2 = 77.5c$

Explanation:

From the question we are told that

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$q=cm \triangle T$

Generally heat released by the iron bolt = heat gained by the iron bolt

Generally solving mathematically

$-(0.45*m* (T_2-100 \textdegree c)) = 0.45*m*(T_2 -55\textdegree c)$

$-(T_2-100 \textdegree c)) = (T_2 -55 \textdegree c)$

$T_2 +T_2= 100 \textdegree c+55 \textdegree c$

$T_2=\frac{155 \textdegree c}{2}$

$T_2 = 77.5 \textdegree c$

Therefore $T_2 = 77.5 \textdegree c$ is the final temperature inside the container

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3 years ago