Download presentation

Presentation is loading. Please wait.

Published byMatthew Crowley Modified over 3 years ago

1
Alternating Current voltage time 0 maximum positive voltage (the peak voltage) maximum negative voltage (peak voltage) Direction of current and size constantly change. Mains frequency is 50 Hz

2
Alternating Current 2 Voltage (V) Time (s) 0 peak voltage effective voltage The quoted value ( rms ) or Effective voltage of an a.c. supply is the same as the steady d.c. voltage which would produce the same heating effect in a resistance wire. The quoted value of the mains voltage in the UK is 230 V. The peak voltage is 325 V. Effective voltage is measured with a voltmeter. Peak voltage is measured with an oscilloscope.

3
Alternating Current 3 The quoted value of an a.c. supply is also known as the r.m.s. value (root mean square). The peak value is 2 larger than this r.m.s. value. This applies to both voltage and current. Voltage Time peak value r.m.s value

4
Alternating Current 4 Peak and r.m.s. values: Example The period of a sinusoidally varying current is 0.005 s. The peak value of the current is 4·0 A. Calculate a) the frequency b) the root mean square value of the current. Frequency = 1 / Period Frequency = 1 / 0.005 Frequency = 200 Hz

5
Calculation of frequency timebase (s cm –1 ) y input 0.02 Find the time for one wave. This is the period. frequency = 1/period Example Time base = 0.02 s cm -1 Period = time base setting x no of boxes for 1 cycle Period = 0.002 x 4 = 0.08 s Frequency = 1 / period Frequency = 1 / 0.08 = 12.5 Hz.

Similar presentations

OK

St Columba’s high School Electricity and Electronics Electric Fields and Resistors in Circuits Alternating Current and Voltage.

St Columba’s high School Electricity and Electronics Electric Fields and Resistors in Circuits Alternating Current and Voltage.

© 2017 SlidePlayer.com Inc.

All rights reserved.

Ads by Google

Ppt on dining etiquette Ppt on water scarcity articles Ppt on earth dam failure Glass fiber post ppt online Ppt on first conditional worksheet Ppt on power line communication scanner Ppt on introduction to object-oriented programming with c++ Ppt on high voltage circuit breaker Ppt on marketing management by philip kotler books Ppt on cross site scripting