Learning this word 怕 which is heart and bright. It means bright and blemishless heart like Brave Heart. Why this is fear heart?
This is a phono-semantic compound. The heart radical is the semantic component. It tells us this has a heart (emotion)-related meaning. The righthand side is the phonetic component. In this case, 白 /bai/ which has a similar sound as 怕 /pa/.
This wikipedia article explains the six different categories of Chinese characters. Check the section on phono-semantic compounds for more examples.
「怕」 (Mandarin Pinyin: pà, Zhengzhang OC: /*pʰraːɡs/, to be afraid) is comprised of two components:
- 「心・忄」 (heart > emotions), a meaning hint; and
- 「白」 (Mandarin Pinyin: bái, Zhengzhang OC: /*braːɡ/), a sound hint.
Note that words have both meaning and sound, and you can't write every word with just a bunch of symbols representing meaning - sounds play a major role in determining what a word is.
Here, 「白」 is only a sound hint, not a meaning hint. To emphasise that 「白」 is only a sound hint, people have written the word represented by 「怕」 differently throughout the ages with different sound hints. For example,