體積V=
4 |
3 |
赤道長度為2πR,線速度v=
2πR |
T |
當(dāng)“雪龍”號到達(dá)南極后,用彈簧秤測量同一個鉤碼的重力,記下彈簧秤的讀數(shù)為F2.
F2=
GMm |
R2 |
當(dāng)“雪龍”號停泊在赤道時,用彈簧秤測量一個鉤碼的重力,記下彈簧秤的讀數(shù)為F1;
F1=
GMm |
R2 |
4π2R |
T2 |
由①②得M=
4π2R3 | ||
(1?
|
所以密度ρ=
M |
V |
3π | ||
(1?
|
答:地球平均密度的表達(dá)式是
3π | ||
(1?
|
4 |
3 |
2πR |
T |
GMm |
R2 |
GMm |
R2 |
4π2R |
T2 |
4π2R3 | ||
(1?
|
M |
V |
3π | ||
(1?
|
3π | ||
(1?
|