额定电压 | 220V | ||
额定功率 | 冷风 | 暖风 | 热风 |
132W | 682W |
(2)已知R2阻值为 44Ω,求电吹风吹热风时的额定功率。
(3)已知电吹风出风口的横截面积为 3×10 -3m2正常工作出风口风速为10m/s,则吹暖风时,吹出来的风的温度升高了多少?(空气的比热容取1.0×103J/(kg·℃)空气的密度取 1.0kg/m3,不计热量损失,结果保留一位小数。)
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