| U |
| R |
| 6V |
| 10Ω |
(2)当开关S闭合后,电阻R1在10s内消耗的电能W=I2Rt=(0.6A)2×4Ω×10s=14.4J;
(3)将两电阻并联后接入原电路,则总电阻是 R并=
| R1R2 |
| R1+R2 |
| 4Ω×6Ω |
| 4Ω+6Ω |
由公式P=
| U2 |
| R并 |
| (6V)2 |
| 2.4Ω |
答:(1)当开关S闭合后,电流表示数为0.6A;
(2)当开关S闭合后,电阻R1在10s内消耗的电能为14.4J;
(3)若将两电阻并联后接入原电路,当开关S闭合后,电路的总功率为15W.

| U |
| R |
| 6V |
| 10Ω |
| R1R2 |
| R1+R2 |
| 4Ω×6Ω |
| 4Ω+6Ω |
| U2 |
| R并 |
| (6V)2 |
| 2.4Ω |