Cho mạch điện có điện trở R =50 Ω , cho dòng điện có cường độ 1,8A qua điện trở . a) tính hđt của nguồn điện . b) thay R bằng R' khi đó cđdđ qua R' giảm ba lần tính R' . c) thay R băng R'' = 15 Ω khi đó cđdđ qua R'' là bao nhiêu?

In positive numbers less than 1, the zeros between the decimal point and non zero are significant

If 2 moles of co_2 at 2l and 500k are expanded reversibly to 20l, more work can be obtained from an adiabatic process than from an isothermal process. is the above statement true or false?

Beryl states that insulation with the smallest possible thermal conductivity is best to keep a house warm in winter, but worst for keeping a house cool in summer. sapphire insists the reverse is true: low thermal conductivity is good in the summer, but bad in the winter. which one, if either is correct? a. beryl, because low thermal conductivity results in low heat transfer. b. beryl, because low thermal conductivity results in high heat transfer. d. sapphire, because low thermal conductivity results in high heat transfer. e. neither, because low heat transfer is desirable both in summer and in winter.