YouTube - Broadcast Yourself.

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Added: 1 year ago
From: cperic88
Views: 187

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Your presentation is so clear.

I really like studying physics since P.5.

Can we make friends? Because I have some question about physics to ask, but my friends don't like physics- -

Henry753951 1 year ago
@Henry753951 Thanks, What is your problem ?

cperic88 1 year ago
This has been flagged as spam show

@cperic88 .....我可能用中文嗎? 其實我只係一個中二(今個9月升中三先學Physics)的香港寧波第二中學的學生。你有沒有MSN／Facebook？我可以點稱呼你？^^ 我依有２個問題想問＠＠其中一個係: 冬天定係夏天的氣壓較大?係咪冷空氣密度較熱空氣的密度高，所以冬天的氣壓較高?你可唔可以詳細講@@(我好似好煩- -) 第二係: 要將250g的水由攝氏80度冷卻到攝氏0度，需要加入幾多(質量)溫度為攝氏零下4度的冰? (冰的比熱容量= 2060J KG-1) 我的估計係：(設要加入 m kg 的冰。) 水釋放的能量=冰吸入的能量 mcT+ml = ml+mcT(水)+mcT(冰) ( 0.25*4200*80 ) + (0.25*3.34*10^5) = [ m*(3.34*10^5) ] + (m*4200*80) + (m*2060*4) m =0.247kg (準確至3位有效數字) Is it right?

Henry753951 1 year ago