紅外幅射和電磁幅射的分別

基本上，電磁輻射即係電磁波，其實只係字面問題 ==
我prefer用電磁波，因為電磁輻射個輻射二字有d恐怖

話得明波，即係一種傳播能量渠道。只係佢係由電場同磁場組成而已

電磁波有不同頻率，不同頻率又有不同叫法
例如收音機、手機o個d叫無線電波，算係比較低頻率 (例如881 = 88.1MHz)
高少少頻率叫微波，即係微波爐用o個款
再高d叫紅外線，又叫紅外輻射
甚至你平時見到ge可見光都係電磁波一種
x光、伽碼射線都係一種，只係頻率高低分別

至於點解會有輻射二字，我諗係因為佢地都係將一d能量向外射出ge關係
當然有無對人體有無殺傷力好睇究竟佢個頻率幾高，同個強度啦
最重要的就係究竟接收能量舊野係咪接收到呢
例如微波爐發ge微波雖然頻率低，但係佢射落d水分子到，d水分子就接收到
所以如果你放隻手入去叮，應該會熟
可見光頻率高，強度吾高，所以又無咩傷害，當然強度高ge laser除外
核幅射ge伽碼射線因為頻率高關係，所以有殺傷力

Electromagnetic waves (or electromagentic radiation 電磁波) are waves that travel by mutual interaction of time varying electric and magnetic fields. Electromagnetic waves ranes from very low frequencies, 30 kHz, to very high frequencies, of order of 10^21 Hz. Such range of frequencies is called an "electromagentic spectrum"(電磁頻譜).

Infrared radiation (紅內線) only occupies a small portion of the electromagentic spectrum. It ranges from frequencies of 3 x10^11 Hz (wavelength 1mm, far infared 遠紅內線) to 3 x 10^14 Hz (wavelength 780 nm, near infared 近紅內線).

Infared radiation gives us a sensation of heat. It is thus commonly called "heat waves".