Calculate the acceleration and displacement when the velocity is 15 ms−1, if x = t
^3 − 12t + 32.
Need help with this.. Calculate the acceleration and displacement when the velocity is 15ms−1, if x=t ^3 − 12t + 32.?
2020-05-20 10:05 pm
回答 (1)
2020-05-20 10:23 pm
✔ 最佳答案
Displacement, x = t³ - 12t + 32Velocity, v = dx/dt = 3t² - 12
Acceleration, a = dv/dt = 6t
When v = 15 m s⁻¹:
3t² - 12 = 15
3t² - 27 = 0
t² - 9 = 0
(t - 3)(t + 3) = 0
t = 3 or t = -3 (rejected)
When t = 3:
Acceleration, a = 6(3) = 18 m/s²
Displacement, x = (3)³ - 12(3) + 32 = 23 m
收錄日期: 2021-04-18 18:30:20
原文連結 [永久失效]:
https://hk.answers.yahoo.com/question/index?qid=20200520140530AAnxsoW