The sinusoidal voltage across a 1 . 0 kΩ resistor has a peak value 325 V . (c) Calculate the average power dissipated in the resistor.

Given, Peak value of voltage V 0 = 325 , Value of resistance R = 1 . 0 K Ω = 1000 Ω Current in the resistor I = V r m s R . Where V r m s = V 0 2 = 325 2 = 230 V ∴ I = 230 1000 = 0 . 23 A . Power dissipated in resistor P = I r m s 2 R = 0 . 23 2 × 1000 = 52 . 9 ≈ 53 W .

MEDIUM

AS and A Level

IMPORTANT

Earn 100

The Y-sensitivity and time-base settings are $5 V / cm$ and $10 ms / cm$ . The trace seen on the $CRO$ screen is the one shown in Figure .

Determine the amplitude, period and frequency of the signal applied to the $Y$ -input of the $CRO$ .

Important Questions on Alternating Currents

EASY

AS and A Level

IMPORTANT

Physics for Cambridge International AS & A Level Coursebook 3rd Edition Digital Access>Chapter 27 - Alternating Currents>Questions>Q 6

Sketch the CRO trace for a sinusoidal voltage of frequency

100 Hz

and ampli tude

10 V

, when the time-base is

10 ms / cm

and the

Y

-sensitivity is

10 V / cm

EASY

AS and A Level

IMPORTANT

Physics for Cambridge International AS & A Level Coursebook 3rd Edition Digital Access>Chapter 27 - Alternating Currents>Questions>Q 7

The alternating current (in ampere, A) in a resistor is represented by the equation:

I = 2.5 \sin (100 πt)

Calculate the r.m.s. value for this alternating current.

EASY

AS and A Level

IMPORTANT

Physics for Cambridge International AS & A Level Coursebook 3rd Edition Digital Access>Chapter 27 - Alternating Currents>Questions>Q 8

The mains supply to domestic consumers in many European countries has an r.m.s. value of

230 V

for the alternating voltage. (Note that it is the r.m.s. value that is generally quoted, not the peak value.) Calculate the peak value of the alternating voltage.

MEDIUM

AS and A Level

IMPORTANT

Physics for Cambridge International AS & A Level Coursebook 3rd Edition Digital Access>Chapter 27 - Alternating Currents>Questions>Q 9

Calculate the average power dissipated in a resistor of resistance

100 Ω

. When a sinusoidal alternating current has a peak value of

3.0 A

EASY

AS and A Level

IMPORTANT

Physics for Cambridge International AS & A Level Coursebook 3rd Edition Digital Access>Chapter 27 - Alternating Currents>Questions>Q 10

The sinusoidal voltage across a $1.0 kΩ$ resistor has a peak value $325 V$ .

(a) Calculate the r.m.s. value of the alternating voltage.

EASY

AS and A Level

IMPORTANT

Physics for Cambridge International AS & A Level Coursebook 3rd Edition Digital Access>Chapter 27 - Alternating Currents>Questions>Q 10

The sinusoidal voltage across a $1.0 kΩ$ resistor has a peak value $325 V$ .

(b) Use $V = I R$ to calculate the r.m.s. current in the resistor.

MEDIUM

AS and A Level

IMPORTANT

Physics for Cambridge International AS & A Level Coursebook 3rd Edition Digital Access>Chapter 27 - Alternating Currents>Questions>Q 10

The sinusoidal voltage across a $1.0 kΩ$ resistor has a peak value $325 V$ .

EASY

AS and A Level

IMPORTANT

Physics for Cambridge International AS & A Level Coursebook 3rd Edition Digital Access>Chapter 27 - Alternating Currents>Questions>Q 10

The sinusoidal voltage across a $1.0 kΩ$ resistor has a peak value $325 V$ . Calculate the peak power dissipated in the resistor.

The Y-sensitivity and time-base settings are 5 V/cm and 10ms/cm. The trace seen on the CRO screen is the one shown in Figure . Determine the amplitude, period and frequency of the signal applied to the Y-input of the CRO.

Important Questions on Alternating Currents

Learn and Prepare for any exam you want !

The Y-sensitivity and time-base settings are $5 V / cm$ and $10 ms / cm$ . The trace seen on the $CRO$ screen is the one shown in Figure .

Determine the amplitude, period and frequency of the signal applied to the $Y$ -input of the $CRO$ .