体积V=
4 |
3 |
赤道长度为2πR,线速度v=
2πR |
T |
当“雪龙”号到达南极后,用弹簧秤测量同一个钩码的重力,记下弹簧秤的读数为F2.
F2=
GMm |
R2 |
当“雪龙”号停泊在赤道时,用弹簧秤测量一个钩码的重力,记下弹簧秤的读数为F1;
F1=
GMm |
R2 |
4π2R |
T2 |
由①②得M=
4π2R3 | ||
(1−
|
所以密度ρ=
M |
V |
3π | ||
(1−
|
答:地球平均密度的表达式是
3π | ||
(1−
|
4 |
3 |
2πR |
T |
GMm |
R2 |
GMm |
R2 |
4π2R |
T2 |
4π2R3 | ||
(1−
|
M |
V |
3π | ||
(1−
|
3π | ||
(1−
|