Here is the pblm, but i can't seem to get a foothold as where to start. I've tried starting with Kirchov's Laws, but can't see to get anywhere with them. Plz help.
*One type of ohmmeter consists of an ammeter connected to a series resistor and a battery. The scale is different from ammeters and voltmeters. Zero resistance correspodns to fullscale deflection (because maximum current flows from the battery), whereas infinite resistance corresponds to no deflection (no current flow). Suppose a 3.0V battery is used, and a glavanometer that has an internal resistance of 25ohms and deflects fullscale for a current of 35 microAmps. What values of shunt resistance, R(shunt), and series resistance, R(series), are needed to make an ohmmeter that registers a midmid scale deflection( that is half the max) for a resistance of 30ohms? [Note: and additional series resistor ( variable) is also needed so the meter can be zeroed. the sero should be checked frequently by touching the leads together, sinc e the battery voltage can vary. Because of battery voltage variation, such ohmmeters are not precision instruments, but they are useful to obtain approx. values.]
*One type of ohmmeter consists of an ammeter connected to a series resistor and a battery. The scale is different from ammeters and voltmeters. Zero resistance correspodns to fullscale deflection (because maximum current flows from the battery), whereas infinite resistance corresponds to no deflection (no current flow). Suppose a 3.0V battery is used, and a glavanometer that has an internal resistance of 25ohms and deflects fullscale for a current of 35 microAmps. What values of shunt resistance, R(shunt), and series resistance, R(series), are needed to make an ohmmeter that registers a midmid scale deflection( that is half the max) for a resistance of 30ohms? [Note: and additional series resistor ( variable) is also needed so the meter can be zeroed. the sero should be checked frequently by touching the leads together, sinc e the battery voltage can vary. Because of battery voltage variation, such ohmmeters are not precision instruments, but they are useful to obtain approx. values.]
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