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Course: Bridge Course Class 12th Physics > Unit 2

Lesson 3: Heat dissipated and Power
Science
Bridge Course Class 12th Physics
Electricity
Heat dissipated and Power
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Heating effects of electric current

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Problem

A steady current, I=0.40 A, flows through the filament of a bulb connected to a 20 V power source.
Find the heat dissipated in the filament, H, in one minute.
Note: Use S.I. units to get the answer in Joules (J).
H=
  • Your answer should be
  • an integer, like 6
  • a simplified proper fraction, like 3/5
  • a simplified improper fraction, like 7/4
  • a mixed number, like 1 3/4
  • an exact decimal, like 0.75
  • a multiple of pi, like 12 pi or 2/3 pi
J