"Ohm's Law and Its Application" Ohm's Law PPT courseware

Description

"Ohm's Law and Its Application" Ohm's Law PPT courseware

teaching objectives

1. Understand the relationship between two proportions

2. Understand the meaning of the two deformation formulas of Ohm’s law

3. Be able to use Ohm’s law to perform simple calculations

The relationship between current, voltage and resistance:

When the resistance R is constant, the current I is proportional to the voltage U across both ends.

When the voltage U is constant, the current I is inversely proportional to the resistance R.

Ohm's law content:

The current in a conductor is directly proportional to the voltage across the conductor and inversely proportional to the conductor's resistance.

Explanation: Ohm's law reveals the relationship between current and voltage; current and resistance.

The three physical quantities correspond to the same moment and the same conductor (or the same section of circuit).

Application Law: Apply the relationship between current, voltage, and resistance in a circuit

Example 1. We already know that there must be a large resistor in the test pen to limit the current through the human body. There is an existing test pen with a resistance of 880KΩ. The resistance of the neon tube and the resistance of the human body are much smaller than this value and can be ignored. How much current flows through the human body during use?

①Draw a picture according to the meaning of the question;

② Mark the relevant physical quantities on the diagram;

③When answering the question, write down: the known sum, the solution process, and the result (all physical quantities must be in unified international units)

④After completing the questions, analyze their practical significance.

Application 1. Given voltage and resistance, find the current

The voltage of the lathe lighting is 36V, and the resistance of the filament is 30Ω when it works normally. Find the current through the filament.

Problem solving steps:

(1) Draw a circuit diagram

(2) Mark the known conditions and required quantities

(3) Solve

summary

Calculation steps using Ohm's law:

(1) Draw the equivalent circuit diagram

(2) Mark the known conditions on the diagram, and use the same unit (including directly known quantities and indirect known quantities using the current, voltage, and resistance relationships of series and parallel circuits) and the required quantity.

(3) According to Ohm's law, the indirect known quantities are marked for calculation based on the relationship between current, voltage and resistance of series and parallel circuits (the same conductor at the same time)

Format:

(1) "Poetry line" format, that is, left-end alignment

(2) Write formulas, generate data, and get results ("three steps")

Challenge yourself

1. There is a resistor. When a voltage of 4V is applied to both ends of the resistor, the current through the resistor is 2A. If the voltage is changed to 10V, what is the current through the resistor?

Problem breakdown:

① There is a resistor. When a voltage of 4V is applied to both ends of it, the current through the resistor is 2A. What is the value of this resistor?

Solution: R=U/I=4V/2A=2 

② Change the voltage of the resistor in ① to 10 V. What should its current be? How else can you answer it?

Solution: I=U/R=10V/2  =5A

2. When a certain voltage U is applied to both ends of a 10Ω resistor, the current flowing through it is 2A. If this voltage is applied to both ends of a 20Ω resistor, how much should the current be?

Problem breakdown:

① When a certain voltage U is applied to both ends of a 10Ω resistor, the current passing through it is 2A. What should the voltage U be?

Solution: U=I1R1= 2A× 10Ω=20V

② If the voltage in ① is applied to the 20Ω resistor, what should its current be?

Solution: I2=U/R2=20V/20=1A

How else can you answer it?

I1/I2=R2/R1

Keywords: Ohm's Law teaching courseware, Ohm's Law and its application teaching courseware, Lujiao Edition ninth grade physics PPT courseware download, ninth grade physics slide courseware download, Ohm's Law PPT courseware download, Ohm's Law and its application PPT courseware download, .PPT format;

For more information about the "Ohm's Law Ohm's Law and Its Applications" PPT courseware, please click the Ohm's Law ppt Ohm's Law and its Applications ppt tag.

"Ohm's Law and Its Application" Ohm's Law PPT courseware 2:

"Ohm's Law and Its Applications" Ohm's Law PPT Courseware 2 Introduction to the new lesson George Simon Ohm was born in Erlangen, Germany. He was a man of great genius and scientific ambition. He served as a middle school teacher for a long time and always carried out scientific research unremittingly. , make your own instrument...

File Info

Update Time: 2024-06-28

This template belongs to Physics courseware Lu Jiao Edition Ninth Grade Physics Volume 1 industry PPT template

Preview