Students in physics interest group use the equipment shown in the figure to explore the relationship between heat generated by current passing through conductors and resistance and current. Resistance string of two gas tanks (1) The heat generated by the resistor is absorbed by the air, and the volume of heat absorbed by the air expands, so there is a height difference between the left and right sides of the U-shaped tube, so it can be judged from the height difference of the liquid level in the glass tube how much heat is generated by the current passing through the conductor;

(2) Because the resistance wire in the experimental device heats the air, it should be that the air tightness of the device is poor, such as air box leakage and latex tube rupture.

(3) As shown in Figure A, if two resistance wires are connected in series, the current passing through the resistance wires is the same as the power-on time, and the resistance value of the right resistance is large. It is observed that the liquid level difference in the right U-shaped glass tube is large, indicating that the right resistance generates more heat; (4) As shown in Figure B, the right resistance wire is connected in parallel with the other resistance wire, so the resistance of the resistance wires in the left and right air boxes is the same as the power-on time, but the current flowing through the left resistance is large, and it is observed that the liquid level difference in the left U-shaped glass tube is large, which indicates that the left resistance generates more heat;

(5) (1) The electric wire is connected in series with the conductor, and the current passing through them is the same as the electrifying time, but the resistance of the electric wire is large, so it generates more heat; ② When the broken wires are put together, the resistance of the wires decreases. From P=U2R, the actual power of the bulb increases, so the bulb is brighter.

So the answer is:

(1) How much heat is generated by current passing through the conductor;

(2) Air box leaks;

(3) resistance; When the current and power-on time are the same, the greater the resistance of the conductor, the more heat the conductor generates;

(4) current; When the resistance and current-on time of the conductor are the same, the greater the current passing through the conductor, the more heat the conductor generates.

(5) (1) The current and electrifying time of the electric furnace wire and conductor are the same, but the resistance of the electric furnace wire is large, so the electric furnace wire generates more heat; The actual power of the light bulb becomes larger, so the light bulb is brighter.