Một vật có độ lớn 15 N, phương nằm ngang, chiều từ phải sang trái. Hãy biểu diễn các lực tác dụng lên vật theo tỉ xích tùy chọn.

The duration of a photographic flash is related to an rc time constantly

Ohm's law tells you that i = v/r where v is equivalent voltage and r is equivalent resistance of the circuit
since all circuits have the same voltage, your question is really asking which circuit has the lowest total resistance, since the lower the resistance, the higher the current
circuit a has a resistance of 5 ohms; circuit c is in series so has a resistance of 10 ohms; circuit b is in parallel and therefore has a resistance of 2.5 ohms (review your notes on adding resistances in parallel and series); therefore b has the highest current