As shown in the figure, two parallel long and straight wires are respectively connected with current I1 and I2 in opposite directions, and I1

As shown in the figure, two parallel long and straight wires are respectively connected with current I1 and I2 in opposite directions, and I1

The correct answer to this question is C

A long straight wire with strong current is placed parallel above the cathode ray tube, and the current direction is from right to left, as shown in the figure, the cathode ray will ()
A. Deflection to the inside of the paper B. deflection to the outside of the paper C. deflection up D. deflection down

According to the current direction of the electrified wire and the right-hand spiral rule, the electron ray tube is in the magnetic field perpendicular to the paper surface. When the electron flow direction is from left to right, the particle deflects upward according to the left-hand rule

As shown in the figure, two parallel long straight wires are respectively connected with current I1 and I2 in opposite directions, and I1 > I2; a, B, C and D are four points in the plane of a certain cross section of the wire, and a, B and C are coplanar with the two wires; b is between the two wires, and the connecting lines of B and D are perpendicular to the plane of the wire. The point where the magnetic induction intensity may be zero is ()
A. A point B. B point C. C point D. D point

According to the right-handed helix rule, if the direction of the magnetic induction on the same side of the two currents is opposite, it is a or C, and I1 > I2, so the point is far away from I1 and close to I2, so it is C. Therefore, C is selected

There is current in the wire. Why is the potential of each point equal?
I connect an ideal voltage source with a wire, and the voltage source is short circuited. At this time, there is current passing through the circuit. It shows that the constant current field is generated by the potential difference between the two ends of the voltage source, so the electric field force does positive work on the unit positive charge, and the potential decreases
But why is the voltage between any two points on the wire zero?

What you put forward is a contradictory assumption
The condition of ideal voltage source is that the internal resistance of power supply is far less than the external resistance of circuit
When you connect the two ends of a power supply with wires with very small resistance,
The resistance of the circuit is concentrated on the internal resistance of the power supply. At this time, the current work is basically used for the heating of the power supply, so it is very easy to burn the power supply when the power supply is short circuited