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A classmate didn't have an ammeter. He had a power supply voltmeter. The rheostat setting resistance R0 resistance was known. How to measure the small lamp with known rated voltage Experimental circuit diagram experimental steps need to measure the physical quantities and calculation formula! Hurry!
Steps: 1. Connect the power supply, sliding rheostat, setting resistor R0 and bulb in series. 2. Connect the voltmeter to the bulb in parallel. 3. Connect the circuit and adjust the sliding rheostat so that the voltage indication is the rated voltage of small bulb U4. Remove the voltmeter and connect it to R0 in parallel. 5. Record the voltage indication u06
The power supply voltage is 6V and remains unchanged. The resistance value of resistance R is 30ohm. The resistance value of sliding rheostat R1 varies from 0 to 24ohm. The range of ammeter is 0.6A
The minimum allowable modulation value of sliding rheostat access circuit is --- Ω? If I can't do it, I'll be criticized tomorrow
This is actually limited by the range of the ammeter
R=U/I
6V/0.6A=10Ω
The minimum value can be adjusted to 10 Ω. If it is smaller, the ammeter will be out of range
There are a battery pack, an ammeter, a switch, a sliding rheostat whose maximum resistance value is known as R, a resistor RX whose resistance value is unknown and several sections of wire on the experimental table. Please use these devices to try to measure the resistance value of Rx (the ammeter can only be connected at the same position). (1) please draw the circuit diagram for measuring Rx. (2) write out the expression for calculating Rx: Rx=______ ．
(1) Experimental circuit design: connect the sliding rheostat and the resistance to be measured in series, slide the slide to the position of maximum resistance and zero resistance respectively, read out the current representation twice, and list the equations according to Ohm's law to calculate the resistance value of resistance Rx. The circuit diagram is shown in the following figure: (2) experimental steps: ① sliding rheostat
If the supply voltage U remains unchanged, the current indication is 2a, and the resistance of R1 and R2 in parallel is r
And R1: R2 = 4:3, the power consumed by resistance R2 is 2.5W, then the resistance of R2 is?
Because R1: R2 = 4:3, I1: I2 = 3:4
Because I = I1 + I2 = 2A, I2 = 8 / 7a
R2 = 2.5 / (8 / 7) ^ 2 = 245 / 128 Ω
RELATED INFORMATIONS
- 1. As shown in the figure, the power supply voltage U remains unchanged, and the indication of ammeter is 2A. Resistance R1 and R2 are in parallel, equivalent resistance R, and R1: r = 4:3, If the power consumed by resistor R2 is 2.5W. Find the power supply voltage
- 2. Explore the experiment (1) given a power supply, a voltmeter, a constant resistance (known its resistance), a number of switches and wires, try to design a circuit diagram It can measure the resistance of an unknown resistance according to certain steps You want to draw a picture for me~ In addition, the corresponding letters should be used to represent the physical quantities measured by the elder brother Represents each measured physical quantity Can you give me a picture
- 3. Give you a resistance, voltmeter, switch, power supply and wire with known resistance value. Please design an experiment to measure the resistance value of unknown resistance Rx. (1) draw the circuit diagram of the experiment. (2) write the experimental steps. (3) write the expression of Rx. (4) in addition to the method of substitution with known resistance, You can also use switch (or single pole double throw switch), sliding rheostat to solve the unknown resistance. Students use their brains to think, can you use other methods to measure the resistance of the unknown resistance?
- 4. There are the following equipment on the experimental table: a power supply, an ammeter and a voltmeter, a switch, a sliding rheostat, two resistance boxes, fixed resistance and wires with known resistance values. It is required to select appropriate equipment from the experimental table and design an experiment to prove: "when the voltage at both ends of the resistance remains unchanged, the electric power consumed by the resistance is the same as that consumed by the resistance The resistance of the resistance is inversely proportional. Please draw the experimental circuit diagram, write the experimental steps, and design the data recording form
- 5. What is the effect of changing the 100 ohm resistance in series with the ammeter to 200 ohm in the circuit diagram of superposition theorem on the measurement result
- 6. How to judge which electrical appliance is measured by Voltmeter and ammeter As the title I'm sorry. For example, if two switches are closed, which appliance is short circuited, and if two switches are open?
- 7. For the circuit shown in the figure, the power supply voltage remains unchanged, R2 = 60 Ω. When the switch S is off, the indication of the ammeter is 0.5A; when the switch is closed, the indication of the ammeter is 0.6A. Calculate the resistance of R1
- 8. As shown in the figure on the right, R1 = 30 ohm, R2 = 10 ohm. After closing the switch, the indication of ammeter A is 2a to calculate the power supply voltage!
- 9. As shown in the figure, in the circuit, the power supply voltage is constant, R1 = 6 Ω, R2 = 4 Ω. When S1 and S2 are closed, the indication of ammeter A1 is 1a, and the indication of ammeter A is 2.5A. Calculate: (1) the resistance value of resistance R3 and the indication of voltmeter. (2) when S1 and S2 are both open, the indication of ammeter A1, a and voltmeter v
- 10. The power supply voltage is constant, R1 = 6ohm, R2 = 12ohm, sliding rheostat R3 = maximum resistance value 0, ammeter range is 0 ~ 0.6A, voltmeter range is 0 ~ 3V, open S1, close S2, the heat generated by current through R1 within 10 seconds is 60 joules, power supply voltage is u =? Sliding rheostat R3 = maximum resistance 20 ohm
- 11. As shown in the figure, the power supply voltage remains unchanged. When the switches s and S1 are closed, the indication of the ammeter is 1a. When the switch S is closed and the switch S1 is open, the indication of the current is 0.6A. The ratio of the resistance value of resistance R1 to resistance R2 is () A. 3：2B. 2：3C. 5：3D. 3：5
- 12. In the circuit, the resistance R1 is 10 Ω. Close the switch s, the indication of ammeter A1 is 0.3A, and the indication of ammeter A2 is 0.5A Ask: (1) current through resistance R2: (2) power supply voltage please write the process of solving the problem clearly
- 13. In the circuit shown in the figure, both ammeter and voltmeter are ideal ammeter, then the correct one in the following judgment is () --- the one that can understand (A) Rab = RBD, and RBC is the largest, RAC is the smallest, (B) Rab = RCD, and RBC is the largest, RAC is the smallest, (C) RAC = RCD, and RBC is the largest, RAD is the smallest, (D) RAC = RBD, and RBC is the largest, RAD is the smallest, -- see -- the answer is C. I don't quite understand. If the answer is the same, please forgive me for ignoring it
- 14. Why is the measured value greater than the true value when measuring the internal resistance error of ammeter with half bias method
- 15. Why is it necessary to make the half deviation of pointer as big as R resistance when measuring the internal resistance of meter head with half deviation method
- 16. The full scale current of a Ma meter is 1mA, the internal resistance of the meter is 98 Ω, and the shunt resistance is 2 Ω
- 17. Can the ohm range of the multimeter be used to measure the internal resistance of the power supply and the micro ampere meter?
- 18. Why is the sliding rheostat connected by partial voltage in the experiment of drawing volt ampere characteristic curve of small bulb?
- 19. Pay attention when using ammeter
- 20. When measuring the current with a DC ammeter, if the reference direction is inconsistent with the actual direction, what will be displayed? How to correctly judge the measured current direction? Such as the title