"Rheostats" PPT courseware

Description

"Rheostats" PPT courseware

Part One: Rheostat

1. Rheostat: A device used to change the size of resistance

Principle: The size of the resistance changes with the length of the conductor

sliding rheostat

The maximum resistance value of this sliding rheostat is 20Ω, and the maximum current allowed is 2A.

(1) How to draw a sliding rheostat

Give it a try: Insert a sliding rheostat into the circuit and change the resistance.

(1) Connect to C and D (top two)

The current passes through the metal rod CD, and the resistance value of the circuit is equal to 0

The resistance value does not change when the slider P is moved.

(2) Connect A and B (twice)

The current passes through the coil AB, and the resistance value of the connected circuit is the largest.

The resistance value does not change when the slider P is moved.

2. Correct connection method of sliding rheostat

(1) Connect A and D

The current passes through the AP part of the coil. When the slider P is moved to the right, AP becomes longer and the resistance value becomes larger.

(2)Connect A and C

The current passes through the AP part of the coil. When the slider P is moved to the right, AP becomes longer and the resistance value becomes larger.

Rheostat PPT, Part 2: Other Rheostats

When wiring as shown in the figure, how should you turn the knob to increase the current in the circuit?

Should be turned clockwise

fuel gauge

Rotating disk resistance box

1. The resistance value of the resistor box as shown in the figure is _______.

2. The maximum resistance value of this resistance box is ________. The minimum resistance value is _______.

3. Have you seen any other instrument whose reading method is similar to that of a resistance box?

Jack type resistance box

1. The resistance box as shown in the figure has a resistance value of ____ ohms.

2. The maximum resistance value of this resistance box is ____ ohms, and the minimum resistance value is ____ ohms.

Rheostat PPT, Part 3: "Exercise"

1. As shown in the figure is a schematic structural diagram of a sliding varistor. The figure shows a situation when the sliding varistor is connected to the circuit. It can be seen from the figure that at this time, the resistance line connecting the sliding varistor to the circuit is the ______ segment (fill in AP or BP), if the resistance is to be reduced, the slider P will move toward the ______ end.

2. Among the four connection methods as shown in the figure, when the slider P moves to the right, the resistance value of the access circuit increases ()

3. As shown in the figure is an experimental circuit diagram for changing the current intensity of a sliding rheostat. When the slider P moves to the left to dim the light, which two terminals of the sliding rheostat should be connected to the M and N wires in the circuit diagram? ___________________.

How will the current indication change at this time? _______

4. In the circuit as shown in the figure, R is a sliding rheostat, and the power supply voltage is constant. When the slider slides from b to a, how does the indication of the ammeter change? __________

Keywords: Zhejiang Education Edition eighth grade science PPT courseware free download, rheostat PPT download, .PPT format;

For more information about the "Rheistor" PPT courseware, please click the "Rheistor ppt" tab.

"Rheostats" PPT download:

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"Rheostats" PPT:

"Rheistor" PPT Part One Content: Review Resistance (symbol: R) 1. Concept: The obstruction effect of conductors on current flow. The more resistant a conductor is to the flow of electricity, the greater its resistance. 2. Unit: ohm (ohm) (symbol: ) kiloohm (K), megaohm..

"Rheostats" Voltage and Resistance PPT Courseware 2:

"Rheostats" Voltage and Resistance PPT Courseware 2 1. Resistance of the Conductor 1. Resistance: Indicates the resistance of the conductor to the current. 2. The greater the resistance of the conductor, the greater the resistance to the current. 3. The symbol of resistance in the circuit diagram 4. The unit of resistance: ohm symbol 5..

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Update Time: 2024-10-02

This template belongs to science courseware Zhejiang Education Edition Eighth Grade Science Volume 1 industry PPT template

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