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Question 20 Essay Worth 5 points)

What is the power rating of an LED light bulb if 0.50 A flow through it when connected to an 18 V battery?
Remember to identify all data (givens and unknowns), list equations used, show all your work, and include units and the proper number of
significant digits to receive full credit

User Ellisein
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1 Answer

10 votes
10 votes

So, the power rating of that LED light bulb is 9 Watt.

Introduction

Hi ! I will answer your question. This material is about electricity where You are instructed to calculate the rated power of a lamp. Always remember, the power required by the lamp must also be at least the same as the power from the mains so that the light is not too dim or the lamp does not explode.

Formulas Used

In this question, the formula used is the formula for calculating power, which is the product of the voltage and current flowing. It can be seen mathematically as below:


\boxed{\sf{\bold{P = V * I}}} Or


\boxed{\sf{\bold{P = (V^2)/(R)}}}

With the following condition :

  • P = power that needed (Watt or W)
  • V = voltage that used (Volt or V)
  • I = current that flowed (Ampere or A)
  • R = resistance in electric tools (Ohm or
    \sf{\varOmega})

Problem Solving

We know that :

  • V = voltage that used = 18 V
  • I = current that flowed = 0.50 A

What was asked :

  • P = power that needed = ... W

Step by step :


\sf{P = V * I}


\sf{P = 18 * 0.5}


\boxed{\sf{P = 9 \: Watt}}

Conclusion :

So, the power rating of that LED light bulb is 9 Watt.

User Alysa
by
3.0k points