A car travels along a straight line at 63 kmh ^ -1. When driver notices the traffic light ahead turns red, he breaks the car with uniform deceleration at once. The car travels a distance of 30m b4 it stops just in front of the traffic light. Find the deceleration of the car
點解u = 63/3.6 ms-1??
phy-acceleration
2007-10-08 3:05 am
回答 (2)
2007-10-08 5:28 am
✔ 最佳答案
from the question: 63 km h-1 is the initial velocity of the car beforce the driver braked the car.
0 km h-1 is the final velocity of the car beacuse the driver braked the car.
In PHY, u stands for initial velocity while v stands for final velocity
( u and v are bold letters as they are vectors)
you should note it carefully while applying physic formulae
2007-10-08 3:15 am
63km/h=63000m/3600s=63/3.6m/s
km/h同ms-1是有個constant差(3.6)
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km/h=m/s x 3.6
km/h同ms-1是有個constant差(3.6)
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km/h=m/s x 3.6
收錄日期: 2021-04-13 13:48:28
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