# Homework Help: Voltage vs. Time

1. Sep 18, 2010

### J89

1. The problem statement, all variables and given/known data

Your lab partner is opening and closing the tap switch to turn on and off the voltage from a battery. If you see the following trace on the screen and the VOLTS/DIV knob is set to 0.5 V and the TIME/DIV dial is set to 2s/DIV, you can tell that the voltage of the battery is approximately how many volts?

2. Relevant equations
No known equations that I know of...

3. The attempt at a solution

Well we know that the y axis is all together .5 volts, and the x axis is 2 seconds..so it would common to just multiply .5 by 2..however, it's not one of the choices. So I thought that in the graph since there are three tick marks, you would divide .5/3 and 2/3 and then multiply that together..still did not get it correct..I don't know what I am doing wrong, that was how I was shown it was done.

#### Attached Files:

• ###### square.jpg
File size:
14.9 KB
Views:
132
2. Sep 19, 2010

### Staff: Mentor

Time scale is unrelated to the problem.

Your signal seems to be almost three ticks high, doesn't it? And there is 0.5V per tick, yes?

That's not different from using a ruler to measure something.