What resistance should an ideal ammeter have?

What resistance should an ideal voltmeter have?

Should an ammeter be connected in series or in parallel with the element whose current is measured?

Should a voltmeter be connected in series or in parallel with the element whose voltage is measured?

A \(10.0\,\Omega\) resistor is connected to an ideal \(5.0\,\mathrm{V}\) source. The true current is measured with an ammeter of resistance \(0.50\,\Omega\). What current does the ammeter read, and what is the percent error relative to the undisturbed current?

A divider has \(6.0\,\mathrm{k}\Omega\) on top and \(6.0\,\mathrm{k}\Omega\) on bottom across \(12\,\mathrm{V}\). A voltmeter of resistance \(6.0\,\mathrm{k}\Omega\) is connected across the bottom resistor. Find the loaded reading.

A galvanometer has \(R_g=50\,\Omega\) and full-scale current \(I_g=1.0\,\mathrm{mA}\). What shunt resistance converts it into a \(1.0\,\mathrm{A}\) ammeter?

A galvanometer has \(R_g=100\,\Omega\) and \(I_g=50\,\mu\mathrm{A}\). What series multiplier converts it into a \(10\,\mathrm{V}\) voltmeter?

A \(10\,\mathrm{V}\) divider has \(100\,\mathrm{k}\Omega\) on top and \(100\,\mathrm{k}\Omega\) on bottom. A \(1.0\,\mathrm{M}\Omega\) voltmeter measures the bottom resistor. Find the measured voltage.

Why is it dangerous to connect an ammeter directly in parallel with a low-resistance source?

Why should a voltmeter have a resistance much larger than the resistance it measures across?

A \(2.0\,\Omega\) circuit is powered by \(6.0\,\mathrm{V}\). An ammeter with \(0.20\,\Omega\) resistance is inserted in series. Find the true current without the meter and the current with the meter.

A voltmeter has sensitivity \(20\,\mathrm{k}\Omega/\mathrm{V}\). What is its resistance on the \(10\,\mathrm{V}\) range?

Derive the ammeter shunt formula \(R_s=\frac{I_gR_g}{I-I_g}\).

Derive the voltmeter multiplier formula \(R_m=\frac{V}{I_g}-R_g\).

A meter movement has \(I_g=100\,\mu\mathrm{A}\) and \(R_g=1.0\,\mathrm{k}\Omega\). What voltage makes the bare movement full scale?

Using the same \(I_g=100\,\mu\mathrm{A}\), \(R_g=1.0\,\mathrm{k}\Omega\) movement, find the series resistor needed for a \(5.0\,\mathrm{V}\) voltmeter range.

Using the same \(I_g=100\,\mu\mathrm{A}\), \(R_g=1.0\,\mathrm{k}\Omega\) movement, find the shunt resistor needed for a \(10.0\,\mathrm{mA}\) ammeter range.

An unknown resistor has a voltmeter connected across it. The voltmeter reads \(10.0\,\mathrm{V}\) and has resistance \(1.0\,\mathrm{k}\Omega\). An ammeter outside the parallel combination reads \(0.210\,\mathrm{A}\). Find the unknown resistance after correcting for voltmeter current.

In the ammeter-voltmeter method for measuring resistance, compare the preferred meter arrangement for a very low resistance with the preferred arrangement for a very high resistance. Explain the error being minimized in each case.