第6條肯定係B bor P=Fv,v has a constant slope. (a=constant) hence P/t should be also constant (Given that Force is constant)
第20條又肯定係B two bulb are connected parallel, hence they must have same potential difference lower power rating requires a p.d. of 6V, hence total current drawn=6/6+6/4=2.5A
第41又似乎係B 首先 P=2(V^2 / R) 然後 P=2( (0.5V)^2 / R) [in series p.d. are shared] P=0.5(V^2 / R)
第6條肯定係B bor P=Fv,v has a constant slope. (a=constant) hence P/t should be also constant (Given that Force is constant)
第20條又肯定係B two bulb are connected parallel, hence they must have ...
據很多人解釋 第6條,有a,點用到p=fv,而且佢每秒移動既s都唔同,即係功=fs,即係c果個
20條:C VOLTMETER個R係勁大~所以IN SERIES一定會搶哂12V 而IN SERIES既兩個R 因為一樣RESISTANCE~分到6V 或 in parallel so P=I^2R 24=I^2(6) 9=I^2(4) I=2 I=1.5 I drawn from power supply=2+1.5 =3.5A
有另一個版本 As there is a word "within" there, so only resistance can work on that question. Therefore current flown = 2.5A ..姐係B
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