The following statement about the application of electromagnetic waves is wrong: The bath bomb in th

A. The thermal effect of infrared rays is very strong, and the bath bomb in the family bathroom warms people mainly because it radiates a large amount of infrared rays, so A is correct and does not conform to the topic;

B. Ultraviolet rays have a sterilizing effect, can kill microorganisms, and make disinfection lamps to disinfect Therefore, B is correct and does not conform to the topic;

C. In the process of propagation, electromagnetic waves can transmit many signals such as sound and image, so C is correct and does not conform to the topic;

D. Electromagnetic wave velocity = wavelength frequency, electromagnetic wave velocity is certain, and has nothing to do with wavelength and frequency, so D is wrong and in line with the topic;

So choose D

A. The thermal effect of infrared rays is very strong, and the bath bomb in the family bathroom warms people mainly because it radiates a large amount of infrared rays, so A is correct;

B. Ultraviolet rays have a sterilizing effect, which can kill microorganisms and make a disinfection lamp to disinfect, so B is correct;

C. When the radar is working, it first emits electromagnetic waves, and in the process of propagating forward, it is launched back after encountering obstacles, that is, the radar judges the situation of the object in front according to the electromagnetic waves it receives and reflects the situation The radar uses the reflection of microwaves to detect the direction and distance of the enemy aircraft, so C is correct;

D. Electromagnetic wave speed = wavelength frequency, electromagnetic wave speed is certain, the higher the frequency, the shorter the wavelength, the statement is wrong, in line with the topic;

So choose D