Q1 Marilyn cycles at an average speed of 10.5 ms^-1 around a circular track in anticlockwise direction from A .She stops after 3 minutes.The radius of the circular track is 400m.
The figure is :http://s55.photobucket.com/albums/g155/kwy_candy/?action=view¤t=7.jpg
a) what is the distance travelled by Marilyn?
b) what is her average velocity?
請列式及答案！
physics
2007-09-22 7:21 pm
回答 (1)
2007-09-22 8:00 pm
✔ 最佳答案
a,佢以10.5ms^-1既速度跑左3mins = 180s所以佢跑左既distance係
10.5x180 = 1890m
The distance travelled by Marilyn is 1890m
個track既radius係400,圓周 = 2(3.1415926539793....)r
=2(3.1415926539793...)400
=2510m(corr.to.3sig.)
1890/2510 = 0.750(corr.to.3sig.)
佢跑左3/4個圈
according to the figure,
400^2+400^2 = s^2
displacement = 566
v = s/t
v = 566/60x3
v = 3.14ms^-1(corr.to 3sig.)
參考: My Physics Knowledge
收錄日期: 2021-05-03 06:06:24
原文連結 [永久失效]:
https://hk.answers.yahoo.com/question/index?qid=20070922000051KK01289