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just olya [345]

3 years ago

6

An electric heater is operated by applying a potential difference of 78.0 V across a nichrome wire of total resistance 7.00 Ω. a

) Find the current in the wire. Answer in units of A.
b) Find the power rating of the heater. Answer in units of W.

1 answer:

aleksley [76]3 years ago

8 0

PART A)

Here we know that

potential difference across the wire is

$V = 78 volts$

resistance of wire is

$R = 7 ohm$

now by ohm's law

$V = iR$

$78 = i(7 ohm)$

$i = 11.14 A$

Part b)

Power rating is defined as rate of electrical energy

it is defined as

$P = iV$

now we have

$P = 11.14 ( 78)$

$P = 869.1 Watt$

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Solution:
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4 years ago

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3 years ago

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Answer:

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5 0

3 years ago