Measuring the resistance of a small light bulb will make it easier to enter The following experimental equipments are given: an ammeter (0-0.6a, 0-3A), a voltmeter (0-3v, 0-15v), a sliding rheostat (0-20V), a power supply (6V), a switch, and several wires. When measuring the resistance of 8 Ω with the above-mentioned instruments, the ammeter should not exceed its range, And the pointer of the meter can exceed (or close to) the center line of the surface dial. In the experiment, the resistance value of the sliding rheostat should not be less than?

Measuring the resistance of a small light bulb will make it easier to enter The following experimental equipments are given: an ammeter (0-0.6a, 0-3A), a voltmeter (0-3v, 0-15v), a sliding rheostat (0-20V), a power supply (6V), a switch, and several wires. When measuring the resistance of 8 Ω with the above-mentioned instruments, the ammeter should not exceed its range, And the pointer of the meter can exceed (or close to) the center line of the surface dial. In the experiment, the resistance value of the sliding rheostat should not be less than?

Ammeter 0-0.6a voltmeter 0-3A is more accurate. Although the total current and voltage exceed the maximum value of ammeter and voltmeter, there can be a sliding rheostat. In the test, the sliding current does not exceed 0.3A, r = u / I = 6 / 0.3 = 20 ohm ∵ total resistance in series circuit = sum of resistance of all parts ∵ r rheostat = R total - R fixed value resistance = 2

When trying to touch, which range should be selected? If the charge passing through a conductor is 90C in one minute, what is the current passing through the conductor? The lithium-ion battery of the mobile phone has "60mA · H", is the battery capacity of the mobile phone good or small?

1.5A is the capacity. The larger the battery capacity, the better Be moderate Or it will burn!

I can't get the questions. I failed in the last exam. Please tell me how to analyze. I will take the monthly exam next week. I really don't want to fail again!

Do more questions, so that the formula is familiar, in fact, physics is half a liberal arts, mainly understanding and formula, are simple, electricity, see the topic is to know how to connect the circuit, there is a diagram must analyze the circuit diagram, and then there are three words: set formula! Junior high school physics is simple dead, as long as you want to learn will always learn, unless that has a problem, do you say

The format of solving the problem of physics electricity in the second grade of junior high school
RT
Our teacher said that when writing big calculation questions, the marking teacher should not only look at the answers, but also look at the format, but what kind of format is the calculation question?

For example, using Ohm's law to find the known voltage: r =... I =
Seeking u
u=IR
U =... Times
We get u =
A;