oscillscope

Question 1

how can we measure an alternating voltage?

Answer 1

• using an oscilloscope
• show show voltage varies with time

Question 2

what does the y-gain represent?

Answer 2

• the number of volts represented by the height of each sqaure

Question 3

what is peak voltage?

Answer 3

• the magnitude of the maximum or minimum voltage

Question 4

what is peak to peak voltage?

Answer 4

• difference between the maximum and minimum voltage

Question 5

how can we reduce the uncertainty in reading from the trace

Answer 5

• change the y-gain to make the trace as big as possible

Question 6

what happens when we halve the volts per division?

Answer 6

• doubles the height of the trace
• doesnt affect peak voltage

Question 7

what is the time base

Answer 7

• controls the amount of time represented by the width of each square

Question 8

how can we measure the time period / frequency from an oscilliscope reading

Answer 8

• measure the number of boxes between one cycle
• compare it to the time base
• T = the answer
• f = 1/T

Question 9

what happens if we increase the time base?

Answer 9

• trace gets squashed horizontally
• no effect on time period itself

Question 10

what happens if we switch off the time base

Answer 10

• we get a straight vertical line
• height represents peak-to-peak voltage

Question 11

how can we determine the power transferred by an AC supply

Answer 11

• use the mean power
• half of the peak power

Question 12

what are the three equations to calculate mean power

Answer 12

IoVo / 2

Vo^2 / 2R

Io^2R / 2

Question 13

what is root mean square voltage

Answer 13

• equivalent DC voltage that would produce the same power
• peak voltage / 2

Question 14

what is root mean square current

Answer 14

• equivalent DC current that would produce the same power
• peak current / root 2