Some meters, of course, are more accurate than others! A circuit is wired with a power supply, a resistor and an ammeter for measuring current.
Compare this calculated figure with the measured figure for circuit voltage: A terminal strip is shown in the illustration, but any form of circuit construction is okay. The ammeter reads a current of 24 mA milliAmps.
Set your multimeter to the appropriate voltage range and measure voltage across the resistor as it is being powered by the battery. Also note the simple mathematical relationship between changes in resistor value and changes in circuit current. Voltage should remain approximately the same for any resistor size inserted into the circuit, because it is the nature of a battery to maintain voltage at a constant level.
Be sure not to hold the resistor terminals when measuring resistance, or else your hand-to-hand body resistance will influence the measurement! So the new current can be found by tripling and then doubling the old current of 24 mA. Select the best current range: If your multimeter is autoranging, of course, you need not bother with setting ranges.
Any differences in respective quantities of voltage, current, or resistance are most likely due to meter inaccuracies. So the new current can be found by halving and then halving again the old current of 24 mA.
But current is also inversely proportional to the resistance; a doubling of the resistance will halve the current. Set your multimeter to the highest current range available.
Break the circuit and connect the ammeter within that break, so it becomes a part of the circuit, in series with the battery and resistor. See Answer A circuit is wired with a power supply, a resistor and an ammeter for measuring current.
Record this resistance value for future use.
Substitute different resistors in the circuit and re-take all resistance, voltage, and current measurements. Re-calculate these figures and check for agreement with the experimental data measured quantities.
But current is also inversely proportional to the resistance; a halving of the resistance will double the current. These two factors offset each other and there is no overall change in the current. Record this current value along with the resistance and voltage values previously recorded.
B Current is directly proportional to the voltage. When a voltage of V is impressed across an electric heater, a current of Build a one-battery, one-resistor circuit. Determine the new current if the voltage of the power supply was There should be close agreement between all measured and all calculated figures.
These differences should be rather small, no more than several percent. Compare this calculated figure with the measured figure for circuit resistance: Compare this calculated figure with the measured figure for circuit current: A fourfold increase in the voltage would cause a fourfold increase in the current.4.
Change the ohm resistor with 82 and ohm resistor variedly and repeat step 3. 5. Change the value of electromotive force into 6 V. 6. Repeat steps 3 and 4 (use ohm resistor instead of ohm resistor, because the value of ohm resistor is too small for 6V of electromotive force).
7. The amount of water in the tank is the same as the other tank, so, using Ohm’s Law, our equation for the tank with the narrow hose is But what is the current? Because the resistance is greater, and the voltage is the same, this gives us.
Use the Ohm's law equation to provide numerical answers to the following questions: a. An electrical device with a resistance of Ω will allow a current of amps to flow through it if a voltage drop of ________ Volts is impressed across the device.
Ohm’s Law III—Resistors in Series and Parallel However, all wires that make connections and the connections themselves qualify as series resistance.
CONFIRMING OHM’S LAW BY ALEX KUCHMENKO Aim – To Confirm Ohm’s Law through experimentation. Hypothesis – The More Ohms the resistor has, the weaker the current will become. Materials – Power pack, ammeter, voltmeter, resistors, connecting wires. OHM’S LAW – Sample ReportNAMESECTION #Group Members:OBJECTIVETo experimentally verify Ohm’s Law through measurement and to confirm findings by comparingmeasure.Download