The physics and electricity part will not, what to do!

Don't be afraid of him. Did you study electricity in the second year of junior high school? What grade did you start studying physics?

But I can start with the third year of junior high school. Electricity and work are important knowledge points in the third year of junior high school, and electricity is both the key and the difficult. The first point:

There are two ways to connect circuits: series and parallel.

The second point is to correctly understand the main uses of ammeters, voltmeters and sliding rheostats.

Point 3: That's the point! Understand and become proficient in Ohm's law, understand the relationship between current, voltage and resistance and the related calculations.

The main takeaways are divided into three main points. 1. The development of Oersted, that is, the magnetic effect of electric current, mainly understands its definition, the structure of electromagnets, the factors affecting the strength of magnetism and related applications. 2. The effect of magnetic field on electric current is mainly generator.

If you understand its definition, structure, role and principle, you will know how to use it. 3. Electromagnetic induction phenomenon. Mainly for generators, understand their definition, structure, function and principle.

The most important thing to learn physics is to memorize the main definitions of knowledge points and understand the uses of physics. And skillful in the knowledge of physics.

I wish the landlord a happy study.

Read more books to understand the meaning of electricity concepts and laws, do more questions, and don't ask the teacher. It is nothing more than the knowledge of electric fields, currents, circuits, etc., which can always be learned by heart.

The electrical problem starts from the basic law of series and parallel, such as: the sum of voltage and the current are equal everywhere in series, which can be described by formulas; The parallel voltage equality and current sum can also be described by the formula; In addition, Ohm's law formula and its derivation formula are easy for you to learn by practicing and doing more questions, I believe you can do it, come on!!

I don't know what stage you have learned now, the voltmeter is connected in parallel, and the current becomes connected in series.

The main thing is to memorize some formulas, basic knowledge, and only after memorizing will you apply it flexibly! Isn't that right, you must learn to draw a circuit diagram when you are doing a problem...

∵p=iu ∴i=p/u

And r=u i pushes out r=u 2 p=1936 at a voltage of 110V.

In the same way, p=u2r=

It's not easy for the landlord to fight.

The re-rated voltage can be calculated directly, but at different voltages, the power is different, the filament temperature is different, and the resistance will also change, and the resistance at 110V is smaller than that at 220V, so at 110V, the calculated value is smaller than the actual value.

25W is the power of the bulb, that is, P=VI and because V=I*R, so P=V*V R

Substituting the data 220*220 25=1936 ohm is the actual resistance of the bulb.

2, The power of the bulb p=v*v r

Substituting data 110 * 110 1936 =

Solution: (1) R=U2 P=48400V 25W=1936 Answer: The bulb resistance is 1936.

2) P=U2 R=12100V 1936 = A: The actual power is.