Galvanometer to Voltmeter Question

AI Thread Summary
To construct a voltmeter using a galvanometer with a coil resistance of 50 ohms that deflects full scale at 3.5 mA, a series resistance must be calculated to allow for a full-scale deflection at 35 volts. The required series resistance can be determined using Ohm's law, where the total voltage (35 V) equals the current (3.5 mA) multiplied by the total resistance (galvanometer resistance plus series resistance). Additionally, the discussion highlights the importance of understanding the principles of ammeters and voltmeters, as well as the behavior of capacitors in parallel for related problems. Participants are encouraged to reference their textbooks for guidance on these concepts. The thread emphasizes the need for a clear understanding of voltage and resistance relationships in circuit design.
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A galvanometer of coil resistance 50 ohms deflects full scale for a current of 3.5 mA. What series resistance should be used with this galvanometer to construct a voltmeter which deflects full scale for 35 Volts?
 
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Capacitors in Parallel

A 9.0 microFaraday and 4.0 microFaraday are connected in parallel, and this combination is connected in series with 12.0 microFaraday capacitor.

1. What is the net capacitance?
2. if 32 V is applied across the whole network, calculate the voltage
across each capacitor.
 
These two questions are the only two in my assignment that I don't know how to approach. I would appreciate some guidance as to how to begin.
 
Begin by opening up the textbook and reading the section on ammeters and voltmeters.
Hint: current of 3.5 mA, voltage 35 V, resistance ?
Then read the section on capacitors in parallel.
 
my partial solutions are too long to type out...
anyways, here is what I have so far... I know its incorrect because it does not differentiate between the Voltage in V=IR and the voltage I need to obtain in the question, the 35.0V...

the text says little to do this problem, it does however mention the maximum voltage the coil can tolerate.. and is also stated in units of Ohms/Volts...which I am not given in the question...

so...this has been my attempt so far...I don't really know how to proceed...
 
Answer the question contained in my hint.
 
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