(1)170cm的同学站上后电阻丝接入电路的电阻值;
(2)电源电压U的大小;
(3)小登在调试身高测量仪的过程中发现,被测者身高改变时电流表和电压表的示数均会发生改变,但电阻丝的功率却可能不变;若身高不同的小双和小语站上该测量仪后,均能使电阻丝功率为9W,求小双和小语的身高差。


同类型试题

y = sin x, x∈R, y∈[–1,1],周期为2π,函数图像以 x = (π/2) + kπ 为对称轴
y = arcsin x, x∈[–1,1], y∈[–π/2,π/2]
sin x = 0 ←→ arcsin x = 0
sin x = 1/2 ←→ arcsin x = π/6
sin x = √2/2 ←→ arcsin x = π/4
sin x = 1 ←→ arcsin x = π/2


y = sin x, x∈R, y∈[–1,1],周期为2π,函数图像以 x = (π/2) + kπ 为对称轴
y = arcsin x, x∈[–1,1], y∈[–π/2,π/2]
sin x = 0 ←→ arcsin x = 0
sin x = 1/2 ←→ arcsin x = π/6
sin x = √2/2 ←→ arcsin x = π/4
sin x = 1 ←→ arcsin x = π/2

