W=
20r |
3000r/kW・h |
1 |
150 |
∵P=
W |
t |
∴吹冷风时的功率
P冷风=
W |
t |
2.4×104J |
2×60s |
(3)电热丝的功率:
P电热=P额-P冷风=600W-200W=400W,
∵P=
U2 |
R |
∴电热丝电阻:
R=
U2 |
P电热 |
(220V)2 |
400W |
答:(1)吹风机吹冷风时的功率是200W;
(2)选配的电热丝的阻值是121Ω.
20r |
3000r/kW・h |
1 |
150 |
W |
t |
W |
t |
2.4×104J |
2×60s |
U2 |
R |
U2 |
P电热 |
(220V)2 |
400W |