
(1)不挂钩码时,调节螺母,使杠杆在
(2)如图甲所示,在A点挂3个钩码,在B点挂
(3)在答题卡的相应位置,画出A点所受拉力的力臂l;
(4)如图乙所示是《天工开物》记载的踏碓(碓:dui,古代的一种给稻谷去壳的工具。用脚连续踏杆的一端,另一端就会连续起落)。踏碓属于

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

