电压计

• 曰(speak; bright cloud)ASSOCIATIVE
• 乚(lightning bolt; hook stroke (downward))ASSOCIATIVE

A flash of lightning bursts bright through the clouds—that is electricity itself!

• 厂(rock face; eaves)RADICAL
• 土(earth; soil; ground)ASSOCIATIVE
• 丶(small dot; weight)ASSOCIATIVE

A rock wall pressing down on the earth like a heavy object applying pressure from above.

• 言(word; speech)RADICAL
• 十(ten)PHONETIC

Calculation is using words to count numbers one by one.