Phedre

Ph\`edre
緣底事, 費嗟呀(aa1)

親切的味道

花椒八角, 蒜頭豆鼓, 薑葱芫荽

Ted Hughes

Agamemnon (Oresteia, p.44):

True praise needs none of these trimmings. And the gods' greatest gift that brings a man to the end of his days in peace is a nose to sniff out such imprudence.

Tereus (Tales from Ovid, p.223):

Revenge had swallowed her whole being. She had plunged into a labyrinth of plotting
where good and evil, right and wrong,
forgot their differences.

Phedre (p.28)

When passion boils, reason evaporates.

Phedre (Act 5, p.72)

Has it occurred to you they may hate you enough to grant it? Sometimes the gods accept our prayers just for the opportunity it gives them to punish us in full, at our own request.

Alcestis (p.9)

When the gods decide on death medicine simply fails. Then the best of doctors becomes a learned book or a stupid book, that nobody can decipher.

All the hospitals on earth become useless monuments. No better than pebbles on a beach.

Alcestis (p.15)

We must pray. God only seems to be silent because we are so deafened by our own babble.

加水問題 (一個物理人的觀點)

有一個水缸, 一隻杯, 一罐汽水.

把一杯水倒進缸中, 水位會升高 2 cm. 若缸中原來的水位為 9.6 cm, 將一罐汽水立於水中後, 水位會升至 11.2 cm.

假設汽水罐高 14 cm, 問要浸沒汽水罐, 需再加多少杯水 ?

(中二數學)

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解答:

放罐前, 水位 9.6 cm, 設水量為 9.6 a.
放罐後, 水位 11.2 cm, 設水量為 11.2 b.
不論放罐與否, 水量相同.
故 9.6a = 11.2b, 調項得 b = 6/7 a.
(按: a 大 b 小, 合理)

要浸沒汽水罐, 需追加的水量為 (14 - 11.2) b, 即 2.8 b. 換算可知, 等於 2.4 a.
由於每杯水的水量為 2a,
所以需再加 1.2 杯水.

註: 假設水缸及汽水罐皆為柱狀


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討論:

本題有趣的是, 解答中的 a 與 b 是指甚麼.

最簡單的講法是, 柱體的底面積. 所以高 9.6 乘以底面積 a, 等於體積 9.6a.

但是, a 與 b 也可以理解為兩套不同的體積單位, 兩套 scale. 就像溫度的單位有攝氏, 有華氏. 同一溫度, 攝氏 'C 華氏 'F 的度數卻有別.

同樣道理, 水量也可以理解為用 a 與 b 兩套單位 (有罐無罐時水的高度) 來表示. 於是解答的關鍵, 在於掌握兩套水量單位之間的轉換.