He put ______ $ 20,000 as a deposit on the beautiful $ 20,000 villa believing that his investment would increase over time.
He put _______ $20,000 as a deposit on the beautiful $200,000 villa believing that his investment would increase over time.
有人试图把电流表接到电源两端测量电源的电流,这种想法对吗?若电流表内阻是0.5Ω,量程是1A,将电流表接到10V的电源上,电流表上将会流过多大的电流?会发生什么后果?