兩靜止物體A和B,其質量比為1:4,若它們受相同的力作用而開始運動,1秒後兩物體動能之比為多少?
回答 (1)
2015-11-20 9:27 am
✔ 最佳答案
a1 = F/m, a2 = F/4mv1 = a1*t = F*t/m, v2 = a2*t = F*t/4m
E1 = 0.5*m*v1^2 = 0.5*(F*t)^2/m
E2 = 0.5*(4m)*v2^2 = 0.5*4m*(F*t)^2/16m^2 = 0.5*(F*t)^2/4m
=> E2/E1 = 4
收錄日期: 2021-04-30 20:19:49
原文連結 [永久失效]:
https://hk.answers.yahoo.com/question/index?qid=20151119060438AAsWira