Zigong m hotel

A, when a fire occurs, the temperature rises, the resistance R2 decreases, and the secondary coil current increases, so the voltage of R 1 increases, and the power of R 1 increases, so A is wrong;

B in case of fire, the temperature rises, the resistance R2 decreases and the secondary coil current increases, so the voltage of R 1 increases. Since the total voltage of the secondary coil remains unchanged, the voltage of R2 decreases, so B is wrong;

C, from the analysis of B, it can be seen that the resistance of the secondary coil decreases and the current of the secondary coil increases, so the current of the primary coil will also increase, so C is wrong;

D. As can be seen from the expression, the effective value of the input voltage is 220V, and the voltage of the transformer is proportional to the number of turns, so the voltage of the secondary coil is 22V, and the voltage at both ends of the secondary coil is measured by the voltmeter V 1, so D is correct.

So choose D.