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Metal conduction refers to the directional movement of free electrons in the metal under voltage, but after the electrons in a power supply, a light bulb and a wire move Where does the electron go to the negative pole? Is there a new electron supplement or is the nucleus charged after the electron is removed
···Man, the flow direction of electrons is from the negative pole to the positive pole... Well, in fact, the flow speed of electrons is very slow... It's about 1cm / s. The whole circuit is a cycle system, and the amount of electrons reaching the positive pole is the same as that flowing out of the negative pole. In the battery, electrons flow from the positive pole to the negative pole, forming a cycle
As for the nuclear problem, the electrons become free electrons after being charged, but they will be recaptured after the voltage disappears
AB is two insulated metal balls. A ball is positively charged and B ball is negatively charged. A copper wire is used to connect the two balls. The direction of the free electrons in the wire? The direction of the current?
Why?
The free electron is negatively charged, so it moves towards the a-ball
The direction of the current is the moving direction of the positive charge, and the negative charge moves to the ball a, which is equivalent to the positive charge moving to the opposite direction, that is, to the ball B, so the current is from a to B
When a resistor is applied with a voltage of 5V at both ends, the current passing through is 0.5A. If the voltage at both ends is increased by 15V, what is the resistance and the current passing through
This is simple. The value of the resistance can be calculated first. Remove the current of 0.5A with a voltage of 5V to get a resistance of 10 Ω. Remove the current of 10 Ω with a voltage of 15V to get a resistance of 1.5A
RELATED INFORMATIONS
- 1. When the voltage applied at both ends of a resistor is 5V, the current passing through it is 0.5A. To make the current passing through the resistor 1a, add it to both ends of the resistor What is the voltage applied at both ends of the resistor? If the voltage at both ends increases to 20V, what is the resistance of the resistor? What is the current passing through it?
- 2. When the voltage applied at both ends of a resistor is 5V, the current passing through it is 0.5A. To make the current passing through the resistor 1a, add it to both ends of the resistor What is the voltage applied at both ends of the resistor? If the voltage at both ends increases to 20V, what is the resistance of the resistor? What is the current passing through it?
- 3. In the circuit shown, given resistance R1 = 4 Ω, R2 = 8 Ω, R3 = 6 Ω, R4 = 12 Ω, voltage US1 = 1.2V, US2 = 3V, use superposition theorem to calculate current I
- 4. Resistance R1 = 7 Ω, R2 = 5 Ω, connected in series at both ends of 12V power supply. At this time, the total resistance of the circuit is_____ Ω, R2 voltage___ 5. In parallel in a 3V circuit, The total resistance after parallel connection is____ Ω, when the current passes through the main road____ A. Comparison of current in R1 and R2____ . [a total of 5 blanks, yes, fill in the blanks = 3 =, no process, no matter]
- 5. When the voltage at both ends of a resistor increases from 3V to 4V, the current through it increases by 1a, and then the current in the conductor is? A
- 6. If 50V voltage is applied at both ends of the resistance, and 20c electric quantity of the resistance passes through the cross section within 10 seconds, the resistance value of the resistance is______ Ω．
- 7. In 5 minutes, if the electric quantity passing through the cross-sectional area of a conductor is 60C, the current passing through the conductor is 60C How much is it There are 20 identical lamps connected in series to a 200V circuit. The current at both ends of each lamp is A .4840V B.10V C.200V D.0.1V
- 8. The voltage at both ends of the conductor is 12 volts. The current passes through the conductor in 5 seconds and does 24 joules of work. During this period, the current passes through the cross section of the conductor
- 9. In physics calculation, the voltage of power supply in series circuit remains unchanged, which means that the voltage is equal everywhere? Is the voltage equal everywhere equal to the supply voltage
- 10. The basic problem of the voltage of the parallel circuit in junior high school physics, physics teacher, please come in, there is an additional is not to say 'the voltage at both ends of each parallel branch in the parallel circuit is equal' Junior three physics parallel circuit voltage basic problem, physics teacher please come in, there are additional It doesn't mean that the voltage at both ends of each parallel branch in a parallel circuit is equal, but why is it equal to the total voltage at both ends of the main circuit? It doesn't mean that the two outgoing branches are equal, but it has to be smaller than the main circuit, just like 2 can't be equal to 2 + 2
- 11. If the current direction in the metal wire AB is from a to B, then the direction of the free electrons in the wire is from a to B___ To___ ．
- 12. Is the direction of current in a metal conductor opposite to that of free electrons?
- 13. The length of the rectangle is 2xcm, the width is 4cm, the length of the trapezoid is xcm, the length of the bottom is 3 times of the length of the top, and the height is 5cm? How much bigger?
- 14. In the middle of a cuboid with a length of 15cm, a width of 8cm and a height of 5cm, a round hole with a diameter of 6cm at the bottom is dug out. What is the surface area of the cuboid after digging out Please answer me quickly
- 15. If the height of the cone is 5cm, then the area of the bottom of the cylinder is () cm;
- 16. The length of a rectangle is 14.8cm. If you increase its length by 6.5cm and keep its width unchanged, the area will increase by 67.6cm2. What is the original area of this rectangle?
- 17. In parallelogram ABCD, BD is perpendicular to ad, ad = 6cm, the area of parallelogram is 24, find the length of BD and AC
- 18. The area of a parallelogram is 30cm & # 178;, and the area of a triangle with the same base and height is () CM & # 178
- 19. The three sides of a right triangle are 6cm, 8cm and 10cm respectively. What's the area of the triangle? What's the area of the bottom side of the triangle with a length of 10cm How many cm is the height?
- 20. The upper bottom of a trapezoid is 12.5cm. Reduce the lower bottom by 3.5cm and change it into a parallelogram. At this time, the area is reduced by 7cm. What is the area of the original trapezoid?