MRS EZRINDA MOHD ZAIHIDEE

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CHAPTER 3 APPLICATION OF INTEGRATION
MRS EZRINDA MOHD ZAIHIDEE FAKULTI KEJ. ELEKTRIK
ELEKTRONIK
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LEARNING OUTCOMES

• By the end of this lecture, students should be
  able to
• Derive the formula for average value by refer to
  the graph.
• solve the given questions using the formula.

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3.1 INTRODUCTION

• currents and voltages often vary with time.
• to know the average value of such a current or
  voltage over some particular time interval.
• using integration.
• root mean square (r.m.s.) ? effective measure
  of the energy transfer of a time-varying
  electrical current.

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3.2 AVERAGE VALUE OF A FUNCTION
h
f(t)
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3.2 AVERAGE VALUE OF A FUNCTION
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3.2 AVERAGE VALUE OF A FUNCTION
EXAMPLE Calculate the average value of the given
functions over the specified interval. (a) (b) (c
) (d) (e) (f)
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LEARNING OUTCOMES

• By the end of this lecture, students should be
  able to
• change the trigonometric functions using double
  angle formula.
• find root mean square values using the given
  formula.

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3.3 ROOT MEAN SQUARE VALUE OF A FUNCTION
If f(t) is defined on a, b, the root mean
square (r.m.s.) value is
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3.3 ROOT MEAN SQUARE VALUE OF A FUNCTION
EXAMPLE Find the r.m.s. value of
across 1, 2.
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3.3 ROOT MEAN SQUARE VALUE OF A FUNCTION
EXAMPLE Find the r.m.s. values of the following
functions. (a) (b) (c)
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